Urinary Bladder: A musculomembranous sac along the URINARY TRACT. URINE flows from the KIDNEYS into the bladder via the ureters (URETER), and is held there until URINATION.Urinary Bladder Neoplasms: Tumors or cancer of the URINARY BLADDER.Urinary Bladder Diseases: Pathological processes of the URINARY BLADDER.Urinary Bladder Calculi: Stones in the URINARY BLADDER; also known as vesical calculi, bladder stones, or cystoliths.Urothelium: The epithelial lining of the URINARY TRACT.Carcinoma, Transitional Cell: A malignant neoplasm derived from TRANSITIONAL EPITHELIAL CELLS, occurring chiefly in the URINARY BLADDER; URETERS; or RENAL PELVIS.Urinary Bladder, Overactive: Symptom of overactive detrusor muscle of the URINARY BLADDER that contracts with abnormally high frequency and urgency. Overactive bladder is characterized by the frequent feeling of needing to urinate during the day, during the night, or both. URINARY INCONTINENCE may or may not be present.Cystitis: Inflammation of the URINARY BLADDER, either from bacterial or non-bacterial causes. Cystitis is usually associated with painful urination (dysuria), increased frequency, urgency, and suprapubic pain.Urinary Bladder Neck Obstruction: Blocked urine flow through the bladder neck, the narrow internal urethral opening at the base of the URINARY BLADDER. Narrowing or strictures of the URETHRA can be congenital or acquired. It is often observed in males with enlarged PROSTATE glands.Urinary Bladder, Neurogenic: Dysfunction of the URINARY BLADDER due to disease of the central or peripheral nervous system pathways involved in the control of URINATION. This is often associated with SPINAL CORD DISEASES, but may also be caused by BRAIN DISEASES or PERIPHERAL NERVE DISEASES.Butylhydroxybutylnitrosamine: A substituted carcinogenic nitrosamine.Urination: Discharge of URINE, liquid waste processed by the KIDNEY, from the body.Urinary Tract: The duct which coveys URINE from the pelvis of the KIDNEY through the URETERS, BLADDER, and URETHRA.Urinary Tract Infections: Inflammatory responses of the epithelium of the URINARY TRACT to microbial invasions. They are often bacterial infections with associated BACTERIURIA and PYURIA.Cystoscopy: Endoscopic examination, therapy or surgery of the urinary bladder.Urinary Incontinence: Involuntary loss of URINE, such as leaking of urine. It is a symptom of various underlying pathological processes. Major types of incontinence include URINARY URGE INCONTINENCE and URINARY STRESS INCONTINENCE.Urinary Catheterization: Passage of a CATHETER into the URINARY BLADDER or kidney.Muscle, Smooth: Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)Urinary Retention: Inability to empty the URINARY BLADDER with voiding (URINATION).Cystectomy: Used for excision of the urinary bladder.Urodynamics: The mechanical laws of fluid dynamics as they apply to urine transport.Bufo marinus: A species of the true toads, Bufonidae, becoming fairly common in the southern United States and almost pantropical. The secretions from the skin glands of this species are very toxic to animals.Administration, Intravesical: The instillation or other administration of drugs into the bladder, usually to treat local disease, including neoplasms.Urine: Liquid by-product of excretion produced in the kidneys, temporarily stored in the bladder until discharge through the URETHRA.Urinary Calculi: Low-density crystals or stones in any part of the URINARY TRACT. Their chemical compositions often include CALCIUM OXALATE, magnesium ammonium phosphate (struvite), CYSTINE, or URIC ACID.Hematuria: Presence of blood in the urine.Muscle Contraction: A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.Urinary Bladder Fistula: An abnormal passage in the URINARY BLADDER or between the bladder and any surrounding organ.Urinary Diversion: Temporary or permanent diversion of the flow of urine through the ureter away from the URINARY BLADDER in the presence of a bladder disease or after cystectomy. There is a variety of techniques: direct anastomosis of ureter and bowel, cutaneous ureterostomy, ileal, jejunal or colon conduit, ureterosigmoidostomy, etc. (From Campbell's Urology, 6th ed, p2654)Urethra: A tube that transports URINE from the URINARY BLADDER to the outside of the body in both the sexes. It also has a reproductive function in the male by providing a passage for SPERM.FANFT: A potent nitrofuran derivative tumor initiator. It causes bladder tumors in all animals studied and is mutagenic to many bacteria.Bladder Exstrophy: A birth defect in which the URINARY BLADDER is malformed and exposed, inside out, and protruded through the ABDOMINAL WALL. It is caused by closure defects involving the top front surface of the bladder, as well as the lower abdominal wall; SKIN; MUSCLES; and the pubic bone.Urinary Incontinence, Stress: Involuntary discharge of URINE as a result of physical activities that increase abdominal pressure on the URINARY BLADDER without detrusor contraction or overdistended bladder. The subtypes are classified by the degree of leakage, descent and opening of the bladder neck and URETHRA without bladder contraction, and sphincter deficiency.Cacodylic Acid: An arsenical that has been used as a dermatologic agent and as an herbicide.Rats, Inbred F344Saccharin: Flavoring agent and non-nutritive sweetener.Urethral Obstruction: Partial or complete blockage in any part of the URETHRA that can lead to difficulty or inability to empty the URINARY BLADDER. It is characterized by an enlarged, often damaged, bladder with frequent urges to void.Cystitis, Interstitial: A condition with recurring discomfort or pain in the URINARY BLADDER and the surrounding pelvic region without an identifiable disease. Severity of pain in interstitial cystitis varies greatly and often is accompanied by increased urination frequency and urgency.Carcinogens: Substances that increase the risk of NEOPLASMS in humans or animals. Both genotoxic chemicals, which affect DNA directly, and nongenotoxic chemicals, which induce neoplasms by other mechanism, are included.Mucous Membrane: An EPITHELIUM with MUCUS-secreting cells, such as GOBLET CELLS. It forms the lining of many body cavities, such as the DIGESTIVE TRACT, the RESPIRATORY TRACT, and the reproductive tract. Mucosa, rich in blood and lymph vessels, comprises an inner epithelium, a middle layer (lamina propria) of loose CONNECTIVE TISSUE, and an outer layer (muscularis mucosae) of SMOOTH MUSCLE CELLS that separates the mucosa from submucosa.Cystostomy: Surgical creation of an opening (stoma) in the URINARY BLADDER for drainage.Muscarinic Antagonists: Drugs that bind to but do not activate MUSCARINIC RECEPTORS, thereby blocking the actions of endogenous ACETYLCHOLINE or exogenous agonists. Muscarinic antagonists have widespread effects including actions on the iris and ciliary muscle of the eye, the heart and blood vessels, secretions of the respiratory tract, GI system, and salivary glands, GI motility, urinary bladder tone, and the central nervous system.Receptor, Muscarinic M3: A subclass of muscarinic receptor that mediates cholinergic-induced contraction in a variety of SMOOTH MUSCLES.Aminobiphenyl Compounds: Biphenyl compounds substituted in any position by one or more amino groups. Permitted are any substituents except fused rings.Ureter: One of a pair of thick-walled tubes that transports urine from the KIDNEY PELVIS to the URINARY BLADDER.Urologic Diseases: Pathological processes of the URINARY TRACT in both males and females.Uroplakin III: A uroplakin subtype that heterodimerizes with UROPLAKIN IB to form a component of the asymmetric unit membrane found in urothelial cells.Papilloma: A circumscribed benign epithelial tumor projecting from the surrounding surface; more precisely, a benign epithelial neoplasm consisting of villous or arborescent outgrowths of fibrovascular stroma covered by neoplastic cells. (Stedman, 25th ed)Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Urinalysis: Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically.Vasopressins: Antidiuretic hormones released by the NEUROHYPOPHYSIS of all vertebrates (structure varies with species) to regulate water balance and OSMOLARITY. In general, vasopressin is a nonapeptide consisting of a six-amino-acid ring with a cysteine 1 to cysteine 6 disulfide bridge or an octapeptide containing a CYSTINE. All mammals have arginine vasopressin except the pig with a lysine at position 8. Vasopressin, a vasoconstrictor, acts on the KIDNEY COLLECTING DUCTS to increase water reabsorption, increase blood volume and blood pressure.Uroplakin II: A uroplakin subtype that heterodimerizes with UROPLAKIN IA to form a component of the asymmetric unit membrane found in urothelial cells.Urologic Surgical Procedures: Surgery performed on the urinary tract or its parts in the male or female. For surgery of the male genitalia, UROLOGIC SURGICAL PROCEDURES, MALE is available.Epithelium: One or more layers of EPITHELIAL CELLS, supported by the basal lamina, which covers the inner or outer surfaces of the body.Cocarcinogenesis: The combination of two or more different factors in the production of cancer.Carbachol: A slowly hydrolyzed CHOLINERGIC AGONIST that acts at both MUSCARINIC RECEPTORS and NICOTINIC RECEPTORS.Kidney: Body organ that filters blood for the secretion of URINE and that regulates ion concentrations.Anti-Infective Agents, Urinary: Substances capable of killing agents causing urinary tract infections or of preventing them from spreading.Pelvis: The space or compartment surrounded by the pelvic girdle (bony pelvis). It is subdivided into the greater pelvis and LESSER PELVIS. The pelvic girdle is formed by the PELVIC BONES and SACRUM.Hypogastric Plexus: A complex network of nerve fibers in the pelvic region. The hypogastric plexus distributes sympathetic fibers from the lumbar paravertebral ganglia and the aortic plexus, parasympathetic fibers from the pelvic nerve, and visceral afferents. The bilateral pelvic plexus is in its lateral extent.Receptor, Muscarinic M2: A specific subtype of muscarinic receptor found in the lower BRAIN, the HEART and in SMOOTH MUSCLE-containing organs. Although present in smooth muscle the M2 muscarinic receptor appears not to be involved in contractile responses.Guinea Pigs: A common name used for the genus Cavia. The most common species is Cavia porcellus which is the domesticated guinea pig used for pets and biomedical research.Urination Disorders: Abnormalities in the process of URINE voiding, including bladder control, frequency of URINATION, as well as the volume and composition of URINE.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Electric Stimulation: Use of electric potential or currents to elicit biological responses.Hyperplasia: An increase in the number of cells in a tissue or organ without tumor formation. It differs from HYPERTROPHY, which is an increase in bulk without an increase in the number of cells.Atropine: An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine.Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Urinary Reservoirs, Continent: Structures which collect and store urine and are emptied by catheterization of a cutaneous stoma or internal diversion to the urethra. The reservoirs are surgically created during procedures for urinary diversion.Flavoxate: A drug that has been used in various urinary syndromes and as an antispasmodic. Its therapeutic usefulness and its mechanism of action are not clear. It may have local anesthetic activity and direct relaxing effects on smooth muscle as well as some activity as a muscarinic antagonist.Anura: An order of the class Amphibia, which includes several families of frogs and toads. They are characterized by well developed hind limbs adapted for jumping, fused head and trunk and webbed toes. The term "toad" is ambiguous and is properly applied only to the family Bufonidae.Urinary Incontinence, Urge: Involuntary discharge of URINE that is associated with an abrupt and strong desire to void. It is usually related to the involuntary contractions of the detrusor muscle of the bladder (detrusor hyperreflexia or detrusor instability).Benzidines: Very toxic industrial chemicals. They are absorbed through the skin, causing lethal blood, bladder, liver, and kidney damage and are potent, broad-spectrum carcinogens in most species.Diagnostic Techniques, Urological: Methods and procedures for the diagnosis of diseases or dysfunction of the urinary tract or its organs or demonstration of its physiological processes.Urography: Radiography of any part of the urinary tract.Hydronephrosis: Abnormal enlargement or swelling of a KIDNEY due to dilation of the KIDNEY CALICES and the KIDNEY PELVIS. It is often associated with obstruction of the URETER or chronic kidney diseases that prevents normal drainage of urine into the URINARY BLADDER.Urachus: An embryonic structure originating from the ALLANTOIS. It is a canal connecting the fetal URINARY BLADDER and the UMBILICUS. It is normally converted into a fibrous cord postnatally. When the canal fails to be filled and remains open (patent urachus), urine leaks through the umbilicus.Sodium: A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.Urology: A surgical specialty concerned with the study, diagnosis, and treatment of diseases of the urinary tract in both sexes, and the genital tract in the male. Common urological problems include urinary obstruction, URINARY INCONTINENCE, infections, and UROGENITAL NEOPLASMS.Nitrosamines: A class of compounds that contain a -NH2 and a -NO radical. Many members of this group have carcinogenic and mutagenic properties.Bufonidae: The family of true toads belonging to the order Anura. The genera include Bufo, Ansonia, Nectophrynoides, and Atelopus.Carcinoma: A malignant neoplasm made up of epithelial cells tending to infiltrate the surrounding tissues and give rise to metastases. It is a histological type of neoplasm but is often wrongly used as a synonym for "cancer." (From Dorland, 27th ed)Tumor Markers, Biological: Molecular products metabolized and secreted by neoplastic tissue and characterized biochemically in cells or body fluids. They are indicators of tumor stage and grade as well as useful for monitoring responses to treatment and predicting recurrence. Many chemical groups are represented including hormones, antigens, amino and nucleic acids, enzymes, polyamines, and specific cell membrane proteins and lipids.Muscarinic Agonists: Drugs that bind to and activate muscarinic cholinergic receptors (RECEPTORS, MUSCARINIC). Muscarinic agonists are most commonly used when it is desirable to increase smooth muscle tone, especially in the GI tract, urinary bladder and the eye. They may also be used to reduce heart rate.Neoplasm Invasiveness: Ability of neoplasms to infiltrate and actively destroy surrounding tissue.Urinary Fistula: An abnormal passage in any part of the URINARY TRACT between itself or with other organs.Kidney Pelvis: The flattened, funnel-shaped expansion connecting the URETER to the KIDNEY CALICES.Receptors, Muscarinic: One of the two major classes of cholinergic receptors. Muscarinic receptors were originally defined by their preference for MUSCARINE over NICOTINE. There are several subtypes (usually M1, M2, M3....) that are characterized by their cellular actions, pharmacology, and molecular biology.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Papilloma, Inverted: A mucosal tumor of the urinary bladder or nasal cavity in which proliferating epithelium is invaginated beneath the surface and is more smoothly rounded than in other papillomas. (Stedman, 25th ed)Urogenital Neoplasms: Tumors or cancer of the UROGENITAL SYSTEM in either the male or the female.Carcinoma in Situ: A lesion with cytological characteristics associated with invasive carcinoma but the tumor cells are confined to the epithelium of origin, without invasion of the basement membrane.Receptors, Purinergic: Cell surface proteins that bind PURINES with high affinity and trigger intracellular changes which influence the behavior of cells. The best characterized classes of purinergic receptors in mammals are the P1 receptors, which prefer ADENOSINE, and the P2 receptors, which prefer ATP or ADP.Capsaicin: An alkylamide found in CAPSICUM that acts at TRPV CATION CHANNELS.Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Neoplasms, Experimental: Experimentally induced new abnormal growth of TISSUES in animals to provide models for studying human neoplasms.Vasotocin: A nonapeptide that contains the ring of OXYTOCIN and the side chain of ARG-VASOPRESSIN with the latter determining the specific recognition of hormone receptors. Vasotocin is the non-mammalian vasopressin-like hormone or antidiuretic hormone regulating water and salt metabolism.Reflex: An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.Urolithiasis: Formation of stones in any part of the URINARY TRACT, usually in the KIDNEY; URINARY BLADDER; or the URETER.Reflex, Abdominal: Contractions of the abdominal muscles upon stimulation of the skin (superficial abdominal reflex) or tapping neighboring bony structures (deep abdominal reflex). The superficial reflex may be weak or absent, for example, after a stroke, a sign of upper (suprasegmental) motor neuron lesions. (Stedman, 25th ed & Best & Taylor's Physiological Basis of Medical Practice, 12th ed, p1073)Methylnitrosourea: A nitrosourea compound with alkylating, carcinogenic, and mutagenic properties.Pyelonephritis: Inflammation of the KIDNEY involving the renal parenchyma (the NEPHRONS); KIDNEY PELVIS; and KIDNEY CALICES. It is characterized by ABDOMINAL PAIN; FEVER; NAUSEA; VOMITING; and occasionally DIARRHEA.Dysuria: Painful URINATION. It is often associated with infections of the lower URINARY TRACT.Urologic Neoplasms: Tumors or cancer of the URINARY TRACT in either the male or the female.Euthanasia, Animal: The killing of animals for reasons of mercy, to control disease transmission or maintain the health of animal populations, or for experimental purposes (ANIMAL EXPERIMENTATION).Adrenergic beta-3 Receptor Agonists: Compounds that bind to and activate ADRENERGIC BETA-3 RECEPTORS.Ureteral Neoplasms: Cancer or tumors of the URETER which may cause obstruction leading to hydroureter, HYDRONEPHROSIS, and PYELONEPHRITIS. HEMATURIA is a common symptom.Muscle Relaxation: That phase of a muscle twitch during which a muscle returns to a resting position.Diamines: Organic chemicals which have two amino groups in an aliphatic chain.Biological Markers: Measurable and quantifiable biological parameters (e.g., specific enzyme concentration, specific hormone concentration, specific gene phenotype distribution in a population, presence of biological substances) which serve as indices for health- and physiology-related assessments, such as disease risk, psychiatric disorders, environmental exposure and its effects, disease diagnosis, metabolic processes, substance abuse, pregnancy, cell line development, epidemiologic studies, etc.DioxolanesMesenchymoma: A mixed mesenchymal tumor composed of two or more mesodermal cellular elements not commonly associated, not counting fibrous tissue as one of the elements. Mesenchymomas are widely distributed in the body and about 75% are malignant. (Dorland, 27th ed; Holland et al., Cancer Medicine, 3d ed, p1866)Neoplasm Staging: Methods which attempt to express in replicable terms the extent of the neoplasm in the patient.CreatinineOxotremorine: A non-hydrolyzed muscarinic agonist used as a research tool.Precancerous Conditions: Pathological processes that tend eventually to become malignant. (From Dorland, 27th ed)Tissue Distribution: Accumulation of a drug or chemical substance in various organs (including those not relevant to its pharmacologic or therapeutic action). This distribution depends on the blood flow or perfusion rate of the organ, the ability of the drug to penetrate organ membranes, tissue specificity, protein binding. The distribution is usually expressed as tissue to plasma ratios.Lower Urinary Tract Symptoms: Symptoms of disorders of the lower urinary tract including frequency, NOCTURIA; urgency, incomplete voiding, and URINARY INCONTINENCE. They are often associated with OVERACTIVE BLADDER; URINARY INCOMPETENCE; and INTERSTITIAL CYSTITIS. Lower urinary tract symptoms in males were traditionally called PROSTATISM.Muscle Hypertonia: Abnormal increase in skeletal or smooth muscle tone. Skeletal muscle hypertonicity may be associated with PYRAMIDAL TRACT lesions or BASAL GANGLIA DISEASES.Bacteriuria: The presence of bacteria in the urine which is normally bacteria-free. These bacteria are from the URINARY TRACT and are not contaminants of the surrounding tissues. Bacteriuria can be symptomatic or asymptomatic. Significant bacteriuria is an indicator of urinary tract infection.Urinary Tract Physiological Phenomena: Properties, functions, and processes of the URINARY TRACT as a whole or of any of its parts.Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Methohexital: An intravenous anesthetic with a short duration of action that may be used for induction of anesthesia.Diverticulum: A pouch or sac developed from a tubular or saccular organ, such as the GASTROINTESTINAL TRACT.Pteridium: A plant genus of the family DENNSTAEDTIACEAE. Members contain ptaquiloside, braxin A1, and braxin B. The name is similar to brake fern (PTERIS).Neurons, Efferent: Neurons which send impulses peripherally to activate muscles or secretory cells.Diuresis: An increase in the excretion of URINE. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Urogenital System: All the organs involved in reproduction and the formation and release of URINE. It includes the kidneys, ureters, BLADDER; URETHRA, and the organs of reproduction - ovaries, UTERUS; FALLOPIAN TUBES; VAGINA; and CLITORIS in women and the testes; SEMINAL VESICLES; PROSTATE; seminal ducts; and PENIS in men.Substance P: An eleven-amino acid neurotransmitter that appears in both the central and peripheral nervous systems. It is involved in transmission of PAIN, causes rapid contractions of the gastrointestinal smooth muscle, and modulates inflammatory and immune responses.Cystotomy: Surgical incision or puncture into a URINARY BLADDER. Cystotomy may be used to remove URINARY CALCULI, or to perform tissue repair and reconstruction.Carcinosarcoma: A malignant neoplasm that contains elements of carcinoma and sarcoma so extensively intermixed as to indicate neoplasia of epithelial and mesenchymal tissue. (Stedman, 25th ed)Adenosine Triphosphate: An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.ButylaminesOsmosis: Tendency of fluids (e.g., water) to move from the less concentrated to the more concentrated side of a semipermeable membrane.Spinal Cord Injuries: Penetrating and non-penetrating injuries to the spinal cord resulting from traumatic external forces (e.g., WOUNDS, GUNSHOT; WHIPLASH INJURIES; etc.).Water-Electrolyte Balance: The balance of fluid in the BODY FLUID COMPARTMENTS; total BODY WATER; BLOOD VOLUME; EXTRACELLULAR SPACE; INTRACELLULAR SPACE, maintained by processes in the body that regulate the intake and excretion of WATER and ELECTROLYTES, particularly SODIUM and POTASSIUM.Arylamine N-Acetyltransferase: An enzyme that catalyzes the transfer of acetyl groups from ACETYL-COA to arylamines. It can also catalyze acetyl transfer between arylamines without COENZYME A and has a wide specificity for aromatic amines, including SEROTONIN. However, arylamine N-acetyltransferase should not be confused with the enzyme ARYLALKYLAMINE N-ACETYLTRANSFERASE which is also referred to as SEROTONIN ACETYLTRANSFERASE.Receptors, Purinergic P2X: A subclass of purinergic P2 receptors that signal by means of a ligand-gated ion channel. They are comprised of three P2X subunits which can be identical (homotrimeric form) or dissimilar (heterotrimeric form).AcroleinPrognosis: A prediction of the probable outcome of a disease based on a individual's condition and the usual course of the disease as seen in similar situations.Urethral Neoplasms: Cancer or tumors of the URETHRA. Benign epithelial tumors of the urethra usually consist of squamous and transitional cells. Primary urethral carcinomas are rare and typically of squamous cells. Urethral carcinoma is the only urological malignancy that is more common in females than in males.Urethral Diseases: Pathological processes involving the URETHRA.Parasympathetic Nervous System: The craniosacral division of the autonomic nervous system. The cell bodies of the parasympathetic preganglionic fibers are in brain stem nuclei and in the sacral spinal cord. They synapse in cranial autonomic ganglia or in terminal ganglia near target organs. The parasympathetic nervous system generally acts to conserve resources and restore homeostasis, often with effects reciprocal to the sympathetic nervous system.Serous Membrane: A thin lining of closed cavities of the body, consisting of a single layer of squamous epithelial cells (MESOTHELIUM) resting on a thin layer of CONNECTIVE TISSUE, and covered with secreted clear fluid from blood and lymph vessels. Major serous membranes in the body include PERICARDIUM; PERITONEUM; and PLEURA.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Urinary Catheters: Catheters inserted into the URINARY BLADDER or kidney for therapeutic or diagnostic purposes.Cholinergic Agonists: Drugs that bind to and activate cholinergic receptors.Neurons, Afferent: Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.