Reserpine is an alkaloid from the roots of Rauwofia serpentina (sarpgandha) indigenous to India which has been used in ‘Ayurvedic’ medicine for centuries. The pure alkaloid was isolated in 1955 and later formed to act by causing CA and 5-HI depletion. Reserpine was a popular antihypertensive of the late 1950s and early 1960s, but is now used only as a pharmacological tool.
Reserpine acts at the membrane of intraneuronal granules which store monoamines (NA, 5-HT, DA) and irreversibly inhibits the active amine transporters so the monoamines are gradually depleted and degraded by MAO. The effects last long after Reserpine is eliminated (hit and run drug) because tissue CA stores are restored only gradually.
Higher doses of this drug deplete CAs and 5-HI in the brain as well; cause sedation and mental depression. Antipsychotic effect (mild) and extrapyramidal symptoms are produced due to DA depletion.
Commercial preparations :
SERPASIL 0.25 mg tab; 1 mg/mi inj.