P171 WATER DEPRIVATION REDUCES WATER INTAKE AND INCREASES SUCROSE INTAKE IN SPONTANEOUSLY HYPERTENSIVE RATS: POSSIBLE MECHANISMS

Background and Objective: Water deprivation (WD), a common situation in wild and human lives, can induce an increase in sucrose palatability in SHR. However, it is not known if SHR also has an increase in sucrose intake after WD and if this intake is related to energy intake, as WD reduces food intake, or to the change in sucrose palatability. Methods: Adult (∼12 weeks) male Holtzman (normotensive, NT) or SHR rats (n = 20/strain) were used. In protocol 1, all rats were first subjected to 24-h WD. Food consumption was measured during WD and was used for the non-water deprived (ND)/food restricted (FD) group to equal energy consumption. Three days after the WD, rats were randomly assigned to the 24-hour WD or the ND/FR group. In protocol 2, animals were implanted with an intraoral cannula and were randomly assigned as above. Results: In the WD condition, water intake was greater in NT (15.9 ± 1.1, vs. SHR: 8.6 ± 0.2 mL/120 min, p < 0.05), whereas sucrose intake was greater in SHR (8.8 ± 0.7, vs. NT: 2.1 ± 1 mL/120 min, p< 0.05). In the ND/FR condition, water intake was very low in both strains, however, SHR had a higher sucrose intake compared to NT (11.5 ± 2.0, vs. NT: 3.3 ± 1.8 mL/120 min; p < 0.05). In NT rats, in the WD condition, there was a decrease in sucrose palatability compared to the ND/FR condition, whereas in SHR palatability was similar in the WD or ND/FR condition. SHR have a greater mean arterial pressure than NT (167 ± 3 vs, NT: 105 ± 2 mmHg). Conclusions: Our results suggest that SHR favours energy intake during WD, since during ND/FR they drank equivalent amount of sucrose. This suggestion is supported by the absence of a greater palatability to sucrose in SHR when food is restricted. Support: CAPES PrINT, FAPESP, CNPq