PL-5 Adrenal Medulla and Stress Response

Which cells produced catecholamines in adrenal medulla.

• Pinealocytes

• Neural crest cells

• Chromaffin cells
• Pituicytes

Which cells produces epinephrine?

• Chromaffin cells with less dense granule

• Chromaffin cells with very dense granule

Catecholamines are derived from this amino acids.

These two enzymes are involved in deactivation of catecholamines.

• Monoamine oxidase (MAO)

• Catechol-O-methyltranferase (COMT)

• Phenylethanolamine-N-methyltransfersae

• DOPA decarboxylase

Excretion forms of catecholamines are

• Vanillyl mandelic acid (VMA)

• DOMA

• Metaneprhine and normetanephrine

• Epinephrine and norepinephrine

Main effects of "Fight-or-Flight" response

• Decreases mesenteric blood flow

• Increases muscular blood flow

• Increases rate of cellular metabolism

• Decreases heart rate

How does catecholamines affect cellular metabolism?

• Increases gluconeogenesis

• Increases glycogenesis

• Increases glycogenolysis

• Increases lipolysis

Epinephrine secretion is increased when

• Stress

• Hypovolaemia

• Hypoglycaemia

• Hypertension

Action of catecholamines in adipose tissue.

• Increase activity of HSL

• Increases the activity of lipoprotein lipase

• Promote lipogenesis

• Promote mobilisation of fatty acids from liver to adipose tissue.

Actions of catecholamines in liver.

• Increases gluconeogeensis and glycogenolysis

• Inhibits glycogenesis

• Promote uptake of glucose into liver

• Promotes mobilisation of fatty acids in liver to adipose tissues