recorded in anesthetized rats. I.c.v. (25cl.O nmol) and microinjection of CRH (200 pmol) into medial preoptic area (MPOA) increased sympathetic nerve activity by 56% (250 pmol, i.c.v.) and by 150% (MPOA). The injection of CRH (200 pmol) into the PVN, LHA, VMN and AHA did not increase the nerve activity. Injection of CRH into MPOA suppressed feeding behavior by 47% below the control in 18-h fasted rats. The results suggest that MPOA may be functionally important in energy balance. Angiotensin/Aldosterone
Synergy and Pigeon Salt Appetite. ALAN N. EPSTEIN and MAURI220 MASSI. University of Pennsylvania, Philadelphia, PA, U.S.A. and University of Camerino, Camerino, Italy. Pigeons drink strong NaCl solution copiously and reliably when they are sodium depleted. Their salt appetite is enhanced by multiple depletions and can be suppressed by blockade of angiotensin II (ANG II) biosynthesis. Sodium replete pigeons express a salt appetite when they are treated with excess amounts of either intraventricular ANG II or systemic aldosterone, and the two hormones synergize to produce the appetite when they are given concurrently at low doses. Changes in the birds’ CSF sodium, on the other hand, do not arouse or suppress their salt intake. Like that of the rat, the salt appetite of the pigeon is governed by a synergy of angiotensin and aldosterone.
Study of the Changes in Energy Expenditure Induced by Restricted Feeding in the Rats. PATRICK EVEN and S. NICOLA’I’DIS. C.N.R.S. UA 637, CoMge de France, Paris.
We have measured in rats the changes in total and background energy expenditure (EE) along two periods of dietary restriction, one light (30%), the other severe (83%). EE, corrected for the differences in BW, appeared identical to that of ad libitum fed rats in lightly restricted rats, and reduced in severely restricted rats. It is concluded that rats lightly restricted do not actively decrease EE, but only use less energy due to BW loss and reduced feeding. In severely restricted animals, the decrease of EE was partly corrected if the EE was also corrected for the difference in food intake. However some signs remained that EE could be indeed decreased after 5 days of severe food restriction.
The Effect of the Previous Glucides and Amino Acids.
on the Thermic
PATRICK EVEN. C.N.R.S. UA 637, CoMge de France,
As the obligatory cost of absorption and metabolism of the nutrients is responsible for the thermic effect of feeding (TEF) and is usually considered as constant, the variations observed on TEF are suggested to result from stimulation of brown adipose tissue (BAT) and to be produced in order to adjust energy expenditure to energy intake. Here, we report that, in rats fed ad libitum with different monotonous diets the thermic effect of glucides and amino-acids increases in relation to the content of the macronutriment in the diet. Because body weight and food intake of these rats were normal under all regime, we assume that these changes in TEF are not due to the activation of BAT, but rather to changes in the efficiency of the metabolic processing of glucides and amino-acids. lschymetric Control of Food Intake: Role of the Intensity of the Cells Power Production. P. EVEN, H. COULAUD and S. NICOLA’iDIS. C.N.R.S. UA 637, Col&ge de France, Paris, France.
The major hypotheses proposed to account for the onset of feeding were challenged by pharmacological inhibition of the utilization of glucose and/or lipids in rats. Respiratory