Hemodynamics, prolactin and catecholamine levels during hemorrhagic shock in dogs pretreated with a prolactin inhibitor (bromocriptine).
Bromocriptin, a dopaminomimetic drug, causing inhibition of prolactin secretion, was used in experiments on haemorrhagic shock in dogs. 5 dogs were treated with bromocriptine (0.4 mg.day-1) for two days; a further 5 dogs were used as control animals. 30% of the blood volume was drawn from each dog. Mean arterial blood pressure, heart rate, central venous pressure, acid-base status, prolactin, GH and catecholamine levels were checked before blood letting and monitored until 1 hour after blood letting. Animals treated with bromocriptine showed a significant decrease of the mean arterial blood pressure and of the prolactin rate and a significant increase of catecholamine levels. Control animals, instead, showed a significant increase of the prolactine and catecholamine rates. The results obtained suggest that bromocriptine can constitute an additional hypotensive factor in subjects with acute haemorrhage. A considerable amount of research work previously carried out has shown a close correlation between stress and hyper-prolactinemia. The increase of prolactinemia and the effects of bromocriptine on this hormone during surgical stress is particularly interesting due to its possible implications (Lanza V. et coll., 1983). In previous experiments involving animals it was found that Prolactin exerts positive chronotropic and hypertensive effects (Horrobin D.F., 1977) whilst bromocriptine is a potent agonist of D2 dopaminergic receptors (Thorner M.O. et coll., 1980). Dopamine was found to be particularly useful in the clinical treatment of shock thus suggesting an involvement of peripheral D2 receptors. On the basis of these observations we have considered it worthwhile to investigate the haemodynamic effects of bromocriptine in haemorrhagic shock.
Lanza
V
V
Servizio di Anestesia e Terapia Intensiva Casa di Cura Buccheri La Ferla FBF, Palermo, Italy.
Palazzadriano
M
M
Scardulla
C
C
Mercadante
S
S
Valdes
L
L
Bellanca
G
G
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001971:Bromocriptine / Q000494:pharmacology*; D002395:Catecholamines / Q000097:blood*; D004285:Dogs; D013006:Growth Hormone / Q000097:blood; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D008297:Male; D011388:Prolactin / Q000097:blood*; D012771:Shock, Hemorrhagic / Q000378:metabolism* / Q000503:physiopathology
D002395:Catecholamines; D001971:Bromocriptine; D011388:Prolactin; D013006:Growth Hormone