Behavioral and physiological responses to dipsogens: A comparative analysis

Rats, gerbils and guinea pigs had water intake and vascular conditions measured after various dipsogenic challenges. Species drank equal (per body weight) volumes of water to extracellular stimuli, but drank differentially to water deprivation and cellular challenges. Rats' drinking following water deprivation was associated with hyperosmolality, while gerbils' and guinea pigs' drinking was closely associated with weight loss. Rats and gerbils represented extremes in response to cellular stimuli, rats showed the lowest drinking thresholds (increased osmolality) — greatest drinking, gerbils showed the highest thresholds — least drinking. Manipulation of renal function resulted in near equivalence of response to cellular stimuli for rats and gerbils. The results are discussed in terms of species similarity and dissimilarity of response to dipsogenic challenges.