Paxilline

Overview

Paxilline is a naturally occurring indole-diterpene alkaloid that is produced by certain species of fungi, particularly those in the genus Penicillium. It is known for its role as a potent blocker of large-conductance calcium-activated potassium channels (BK channels), which are important in various physiological processes.

Chemical Structure and Biosynthesis

Biosynthesis pathway of Paxilline

Paxilline is characterized by its complex polycyclic structure, which includes an indole moiety fused to a diterpene skeleton. The biosynthesis of paxilline involves several enzymatic steps starting from simple precursors such as geranylgeranyl pyrophosphate and tryptophan. The pathway includes cyclization, oxidation, and methylation reactions that lead to the formation of the final paxilline structure.

Biological Activity

Paxilline is primarily known for its ability to inhibit BK channels, which are found in various tissues including the nervous system, muscle, and endocrine glands. By blocking these channels, paxilline can affect muscle contraction, neurotransmitter release, and hormone secretion. This makes it a valuable tool in research for studying the physiological roles of BK channels.

Applications in Research

In the field of neuroscience, paxilline is used to investigate the function of BK channels in neuronal excitability and synaptic transmission. It is also employed in cardiovascular research to study the role of these channels in regulating vascular tone and blood pressure.

Safety and Toxicity

While paxilline is a useful research tool, it is important to handle it with care due to its potential toxicity. Ingestion or improper handling can lead to adverse effects, and it should be used in controlled laboratory settings.

Related Pages

• Indole alkaloid
• Diterpene
• Potassium channel
• Penicillium