Down regulation of the muscarinic cholinergic receptor of the rat prostate following castration

Journal Article · Mon Jul 01 00:00:00 EDT 1985 · J. Urol.; (United States)

OSTI ID:5151715

Shapiro, E; Miller, A R; Lepor, H

Prostatic secretion is dependent upon the integrity of the endocrine and autonomic nervous systems and is dramatically influenced by muscarinic cholinergic analogs. In this study, the authors have used radioligand receptor binding methods on whole tissue homogenates and slide mounted tissue sections of rat prostate to determine whether androgens regulate the density of muscarinic cholinergic receptors in the prostate. The muscarinic cholinergic receptor binding affinities (Kd) of (/sup 3/H) N-methylscopolamine in prostatic homogenates obtained from intact, castrate, and castrate rats receiving testosterone replacement (castrate + T) were similar (0.07 to 0.10 nM). The muscarinic cholinergic receptor binding capacity decreased 73 per cent following castration. Testosterone administration restored the density of muscarinic cholinergic receptors in castrate rats to intact levels. In order to ensure that the loss of receptor density was not due to a decrease in the epithelial: stromal cell ratio, the number of muscarinic cholinergic receptors per unit area of epithelium was determined in the 3 treatment groups using autoradiography on slide mounted tissue sections. The density of muscarinic cholinergic receptors in a unit area of epithelium was decreased 91 per cent following castration. Testosterone administration restored the density of muscarinic cholinergic receptors in the castrate rats to intact levels. The modulation of neurotransmitter receptors by steroid hormones may be a mechanism by which sex steroids regulate biological responsiveness of target tissues.

• Research Organization: Johns Hopkins Hospital, Baltimore, MD
• OSTI ID: 5151715
• Journal Information: J. Urol.; (United States), Vol. 1
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ACETYLCHOLINE
RECEPTORS
PROSTATE
AUTORADIOGRAPHY
BIOCHEMICAL REACTION KINETICS
AFFINITY
ANDROGENS
CASTRATION
CHEMICAL BONDS
EPITHELIUM
HOMOGENATES
LIGANDS
RATS
TESTOSTERONE
TRACER TECHNIQUES
TRITIUM COMPOUNDS
AMINES
AMMONIUM COMPOUNDS
ANDROSTANES
ANIMAL TISSUES
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BODY
DRUGS
ESTERS
GLANDS
HORMONES
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
KETONES
KINETICS
LABELLED COMPOUNDS
MALE GENITALS
MAMMALS
MEDICINE
NEUROREGULATORS
ORGANIC COMPOUNDS
ORGANS
PARASYMPATHOMIMETICS
QUATERNARY COMPOUNDS
REACTION KINETICS
RODENTS
STEROID HORMONES
STEROIDS
SURGERY
TISSUES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques