Psy137HomeostaisThirst

Osmotic thirst ingestion ingestion regulations of

Info iconThis preview shows pages 11–23. Sign up to view the full content.

View Full Document Right Arrow Icon
Osmotic thirst
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
ingestion
Background image of page 12
ingestion
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Regulations of sodium and water intakes are linked The kidneys use sodium to conserve water AVP/ADH increases water permeability of duct resulting in more water retention.
Background image of page 14
OVLT projects: to PVN to stimulate ADH secretion. to LH to stimulate motivational responses via limbic circuit. LH
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Types of Thirst Volumetric Volumetric thirst (water) and salt appetite Baroreceptors in the heart and large blood vessels- stretch receptors Release of ADH Receptors in kidney that detect decreases in blood flow Release of renin Renin coverts angiotensinogen to angiotensin II Angiotensin II Release of AVP/ADH and release of aldosterone by adrenal Increase in blood pressure Initiates drinking and salt appetite
Background image of page 16
Background image of page 17

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Neural Circuit for Thirst The atrial barareceptors send a projection to the nucleus of the solitary tract (NST) The NST projects to the median preoptic nucleus The OVLT (osmoreceptors) and the SFO (angiotensin II) project to the median preoptic nucleus The median preoptic nucleus is where the thirst information goes and it controls drinking behaviors
Background image of page 18
Background image of page 19

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Hypovolemic Thirst The baroreceptors in the heart communicate low pressure to N. Sol. Tract (via vagus nerve) which projects to hypothalamus. Ang II also acts on SFO which projects to hypothalamus. Hypothalamus integrates signals to trigger behavioral effectors (i.e. increase fluid motivation = thirst and increase fluid seeking behavior).
Background image of page 20
Diet determines sodium appetite Herbivores: Obtain sodium from plants (component of cells) But sodium content varies seasonally and from place to place. Carnivores: The animals carnivores eat must maintain their own sodium balance. So the carnivores are not under the same salt pressures as herbivores (except when there is blood loss).
Background image of page 21

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Behavioral Homeostasis Under normal conditions, physiological homeostasis maintains sodium balance (kidney, aldosterone=sodium conservation). When physiological homeostasis fails, behavioral
Background image of page 22
Image of page 23
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page11 / 33

Osmotic thirst ingestion ingestion Regulations of sodium...

This preview shows document pages 11 - 23. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online