L. Fortunlamothe et al., INFLUENCE OF PROLACTIN ON IN-VIVO AND IN-VITRO LIPOLYSIS IN RABBITS, Comparative biochemistry and physiology. Part C, Pharmacology toxicology & endocrinology, 115(2), 1996, pp. 141-147
Three experiments were conducted to assess the influence of prolactin
on lipolysis in rabbits. In vivo, a single injection of 1 mg of ovine
prolactin induces increased plasma glycerol and nonesterified fatty ac
ids concentrations within 30 min (P < 0.01). On the contrary, in vitro
, oPRL did not stimulate glycerol release in isolated adipocytes at ph
ysiological concentrations (under 10(-8) M). In a third experiment, th
e effect of chronic hyperprolactinemia on the adrenergic control of li
polysis was studied (daily subcutaneous injections of 1 mg ovine prola
ctin for 12 days). The weight of perirenal adipose tissue at the end o
f the period of injections was 27% lower in the prolactin-injected (PR
L) rabbits than in the control (CTL) rabbits (88 +/- 15 g vs. 120 +/-
25 g; P < 0.05). Food intake during the period of injections was 28% l
ower in the PRL group than in the CTL group (177 +/- 21 g/d vs. 246 +/
- 13 g/d; P < 0.05). Basal glycerol release was 157% higher in adipocy
tes from PRL rabbits than in those from CTL rabbits (P < 0.05). Stimul
ation of lipolysis with different adrenergic agonists was similar in b
oth groups. These results suggested an indirect influence of prolactin
on adipose tissue lipolysis in rabbits, but mechanisms implicated in
this effect remain to be elucidated. Copyright (C) 1996 Elsevier Scien
ce Inc.