Question

If a person was hung upside down, how would the following be affected compared to when the person was standing up straight?

a) Stroke Volume

b) ANP release

c) Na reabsorption

d) Diuresis

e) Sympathetic activation

Answer 1

Solution:-

a)Stroke volume:- It is volume of blood pumped through left ventricle per beat.

During upside down position blood pressure increases due to gravity so the heart beats get decrease that's why stroke volume also get decrease.

b)ANP is Atrial nutriuretic peptide which produce in myocytes of heart atria which helps in lowering of blood pressure and control electrolyte homeostasis.so during hand down position concentration of ANP release increases as blood pressure increase while in standing position conc of ANP is low as blood pressure is normal in standing position

c)Na reabsorption takes place in ascending limb of loop of Henle in nephron of kidney which helps in osmolarity of body fluid. As above we know that ANP increases as blood pressure increases and ANP inhibits so Na reabsorption so in hand down position ANP is increases in body that's why Na reabsorption decreases.

d)Diuresis:-It is condition in which kidney filter more body fluids which results in increase urine production.It helps in lowering the blood pressure as we know in hang down position blood pressure increases so in this condition Diuresis will increase so urine production gets increase in hang down position.

e) Sympathetic pathway helps in increase in heart rate with the help of catecholamines and epinephrine but in hang down position heart beats get decreses so the parasympathetic system gets activated and sympathetic system gets slow down.