Page 178 - Physiology and Pathophysiology MNU 2024-2025 نظرى
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Clinical pharmacy 2024/2025                  Level 2 Pharm D                       Physiology and Pathophysiology (MD303)
           4-  Bar receptor reflex is activated to attempt to ↑ Pa to normal
                                Orthostatic hypotension
             Fainting on standing

              ➔ May occur in individuals whose Baroreceptor reflex
                  is impaired.

               E.g individuals treated with sympatholytic agents.

                                                         B) hemorrhage [ acute blood loss]
              1-  In blood volume➔ ↓ Pa

              2-  The baroreceptor reflex is activated ➔ ↑
                  Sympathetic, ↓Parasympathetic.

              3-  Arteriolar vasoconstriction & ↓capillary pressure
                  (Pc) ➔ ↑capillary absorption ➔ restore circulating

                  blood volume.
              4-  The rennin – Angiotensin system is activated due to
                  the decrease in renal perfusion blood volume.



















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