The central actions of glycine and strychnine on prolactin and LH secretion
Related Experiment Video
Updated: Aug 18, 2026

Dual Somatic Recordings from Gonadotropin-Releasing Hormone (GnRH) Neurons Identified by Green Fluorescent Protein (GFP) in Hypothalamic Slices
Published on: February 24, 2010
Abstract:
Unanesthetized diestrous female rats were tested for the prolactin response following an intraventricular injection of several doses of the neuroinhibitory amino acid glycine, and the antagonist strychnine. Glycine in doses of 1.0 or 0.1 mumoles increased pituitary prolactin release, significantly elevating plasma hormone levels. Direct pituitary effects for glycine were not observed. Strychnine, a glycine antagonist, was effective in blocking the prolactin release caused by glycine in doses as low as 5 nmoles. Intraventricular glycine administration did not alter pituitary LH release significantly. These studies suggest a central stimulatory role for the neuroinhibitory amino acid glycine in provoking prolactin secretion, and that this effect is strychnine sensitive.
More Related Videos
Related Concept Videos
Direct-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship
The direct-acting...
Direct-Acting Cholinergic Agonists: Pharmacological Actions
Indirect-Acting Cholinergic Agonists: Pharmacological Actions
At the neuromuscular junction, these agents work by inhibiting the breakdown of acetylcholine, allowing it to remain bound to the receptor and bind to nearby receptors. This process leads to repetitive firing of the endplate, causing muscle...
Drugs Acting on Autonomic Ganglia: Stimulants
Ganglionic stimulants activate NM nicotinic receptors in autonomic ganglia, falling into two categories: nicotine mimetics [e.g., lobeline, dimethylpiperazine, tetramethylammonium] and muscarinic receptor agonists [e.g., muscarine, methacholine]. The first category's action is rapid and blocked by nicotinic receptor antagonists, while the second category's action is delayed and blocked by atropine-like agents. Nicotine, an alkaloid, affects the heart rate by stimulating sympathetic or...
Regulation of Hormone Secretion
Humoral stimuli,...
Hormones of the Pituitary Gland
The most abundantly secreted hormone from the anterior lobe is the growth hormone, which controls overall growth by...

