HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Fitzsimons, J. T. Articles by Thornton, S. N. Search for Related Content PubMed PubMed Citation Articles by Fitzsimons, J. T. Articles by Thornton, S. N.

J. T. Fitzsimons, M. Massi^* and S. N. Thornton

Physiological Laboratory, Dowing Street, Cambridge CB2 3EG

1. The pigeon drank copiously after a short latency in response to intracerebro-ventricular (I.C.V.) infusion of angiotensin II dissolved in isotonic NaCl. There were small, insignificant increases in urinary excertion so that the increased water intake caused the pigeon to go into positive fluid balance. Water was chosen in preference to 0·3 M-NaCl, which was also available to drink in these experiments.

2. I.C.V. infusion of angiotensin dissolved in water, or in isotonic or hypertonic solutions of non-eletrolytes, or in KCl or CaCl₂ resulted in about half the water intake produced by angiotensin dissolved in isotonic NaCl.

3. I.C.V. infusion of hypertonic NaCl alone caused drinking. I.C.V. infusion of angiotensin dissolved in hypertonic NaCl caused an amount of water to be drunk that was a simple addition of the amounts drunk in response to angiotensin dissolved in isotonic NaCl and to the extra amount of NaCl.

4. Drinking in response to I.C.V. infusion of two other dipsogenic peptides, eledoisin and physalaemin, was similarly affected by the composition of the solutions in which they were dissolved.

5. The pigeon also drank in response to intravenous (I.V.) infusion of angiotensin II dissolved in isotonic NaCl. Urine flow and sodium excretion increased markedly so that the pigeons just maintained fluid balance.

6. In contrast to the reduction in intake when angiotensin was infused I.C.V. dissolved in hypertonic non-electrolytes, I.V. infusions of angiotensin dissolved in hypertonic non-electrolytes caused enhanced drinking, compared with the corresponding infusions of angiotensin dissolved in isotonic NaCl.

7. Drinking induced by I.V. infusion of angiotensin was little affected by simultaneous I.C.V. infusion of isotonic or hypertonic sucrose, or water, but it was increased by simultaneous I.C.V. infusion of hypertonic NaCl.

8. Drinking responses were partly additive when angiotensin was given by simultaneous I.C.V. and I.V. infusion.

9. The increased urine flow and electrolyte excretion in response to I.V. infusion of angiotensin were little affected by simultaneous I.C.V. infusion of angiotensin.

10. These experiments suggest that in the pigeon there may be separate sets of receptors in the cerebral ventricles for initiating drinking, one set responding to angiotensin, another to hypertonic NaCl. Outside the blood—brain barrier, and accessible to blood-borne substances, there may also be separate sets of receptors, one set responding to angiotensin, another to increases in effective osmolality of the blood.

Present address: Collège de France, 11 Place Marcelin-Berthelot, 75231 Paris Cedex 05, France.

This article has been cited by other articles:

				M. K. Heinz and D. A. Gray Role of plasma ANG II in the excretion of acute sodium load in a bird with salt glands (Anas platyrhynchos) Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2001; 281(1): R346 - R351. [Abstract] [Full Text] [PDF]