Apamin therapeutic effect on Parkinson's disease. Dopamine, which is depleted in this disease, will be released from midbrain dopaminergic neurons when these SK channels are inhibited. SK channels have also been proposed as targets for the treatment of epilepsy, emotional disorders and schizophrenia. Apamin Apamin is an 18 amino acid peptide neurotoxin found in apitoxin (bee venom). Dry bee venom consists of 2–3% of apamin. Apamin selectively blocks SK channels, a type of Ca-activated K channel expressed in the central nervous system. Toxicity is caused by only a few amino acids, these are cysteine, lysine, arginine, arginine and histidine. These amino
Evolution of snake venom protein found in the venom had undergone a deletion of two nucleotide bases which made the venom 50-100 times less toxic than it had been previously. This change was correlated with a change in diet from fish to a diet consisting almost entirely of fish eggs, suggesting that the adaptation to an egg diet had removed the selection pressure needed to maintain a highly toxic venom, allowing the venom genes to accumulate deleterious mutations. A similar venom degradation following a shift to an egg-based diet has been found in the Common egg-eater "Dasypeltis scabra", whose diet consists entirely of birds'