Various compounds with different blocking potencies on histamine H2-receptors were administered to rats both into the carotid (ia) and into the brain ventricles (icv) and their effects on PRL release were evaluated. The drugs were cimetidine, as reference compound, ranitidine, 5 to 7 times as potent, and oxmetidine, 8 to 10 times as potent. PRL was measured in blood samples collected at -15, 0 and +5, +10, +20 and +40 min after treatment. Cimetidine (80 mg/kg) and ranitidine (30 mg/kg), when injected ia as a single bolus, induced prompt increases (P less than 0.01) in PRL. On the contrary, oxmetidine (the most potent H2 antagonist), even at the high dose of 80 mg/kg ia, had no effect on PRL release. When the drugs were given icv (0.2 mumol/rat or 0.8 mumol/rat), none of them caused any significant PRL release. These results suggest that histamine H2-blocking potency is not correlated with PRL release. Furthermore, the PRL-releasing activity of the drugs seems not to be due to any action on the central neural control of PRL secretion. This comparative study shows that it is possible (as with oxmetidine) to achieve complete dissociation of the H2-receptor blocking action from the unwanted PRL-release stimulating effect.

Comparison of the effects of histamine H2-receptor antagonists on prolactin secretion in the rat / C. Netti, F. Guidobono, V. R. Olgiati, V. Sibilia, A. Pecile. - In: ENDOCRINOLOGY. - ISSN 0013-7227. - 113:1(1983 Jul), pp. 412-414. [10.1210/endo-113-1-412]

Comparison of the effects of histamine H2-receptor antagonists on prolactin secretion in the rat

F. Guidobono;V. Sibilia;
1983-07

Abstract

Various compounds with different blocking potencies on histamine H2-receptors were administered to rats both into the carotid (ia) and into the brain ventricles (icv) and their effects on PRL release were evaluated. The drugs were cimetidine, as reference compound, ranitidine, 5 to 7 times as potent, and oxmetidine, 8 to 10 times as potent. PRL was measured in blood samples collected at -15, 0 and +5, +10, +20 and +40 min after treatment. Cimetidine (80 mg/kg) and ranitidine (30 mg/kg), when injected ia as a single bolus, induced prompt increases (P less than 0.01) in PRL. On the contrary, oxmetidine (the most potent H2 antagonist), even at the high dose of 80 mg/kg ia, had no effect on PRL release. When the drugs were given icv (0.2 mumol/rat or 0.8 mumol/rat), none of them caused any significant PRL release. These results suggest that histamine H2-blocking potency is not correlated with PRL release. Furthermore, the PRL-releasing activity of the drugs seems not to be due to any action on the central neural control of PRL secretion. This comparative study shows that it is possible (as with oxmetidine) to achieve complete dissociation of the H2-receptor blocking action from the unwanted PRL-release stimulating effect.
Rats, Inbred Strains; Rats; Prolactin; Animals; Ranitidine; Receptors, Histamine; Receptors, Histamine H2; Furans; Cimetidine; Male; Imidazoles
Settore BIO/14 - Farmacologia
ENDOCRINOLOGY
Article (author)
File in questo prodotto:
Non ci sono file associati a questo prodotto.
Pubblicazioni consigliate

Caricamento pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/2434/182514
Citazioni
  • ???jsp.display-item.citation.pmc??? 0
  • Scopus 9
  • ???jsp.display-item.citation.isi??? 13
social impact