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Renin Angiotensin Mechanism.

Pineal Gland.

 


  • The pineal gland is located in the epithalamus, near the center of the brain, between the two hemispheres.

  • Pinealocytes: the cells of Pineal gland secrete a hormone called “Melatonin”.

  • Melatonin is responsible for induction of sleep and wakefulness.

  • Secretion of melatonin is dependent on light.

  • Day light causes decreased blood levels of melatonin and induces wakefulness.

  • As light starts to fall after evening, blood levels of Melatonin start rising, inducing sleep.

  • It helps in maintaining circadian rhythms of the body.

  • It promotes growth and also possesses antioxidant action.

  • Its supplements are used to treat jet lags.
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