Guineesine (or guineensine) is a compound isolated from long pepper (Piper longum) and black pepper (Piper nigrum).
It was first isolated, studied and named from Piper guineense.
Guineensine inhibits the cellular reuptake of anandamide and 2-arachidonoylglycerol in a mouse model (EC<sub>50</sub> = 290âÂÂnM). This causes an increase in the activity of the two neurotransmitters which are classified as endogenous cannabinoids.
Guineesine can dose-dependently produce cannabimimetic effects in a mouse model which are indicated by potent catatonic, analgesic, hypo-locomotive and hypo-thermic effects. In addition, the analgesic and catatonic effects were reversed by the cannabinoid receptor type 1 (CB<sub>1</sub>) inverse agonist rimonabant.
Guineesine is also a monoamine oxidase inhibitor (MAOI) in vitro (IC<sub>50</sub> = 139.2 üM).