Please enable JavaScript.
Coggle requires JavaScript to display documents.
Neuroactive Peptides (Largest family of neurotransmitters - inhibitory or…
Neuroactive Peptides
Largest family of neurotransmitters - inhibitory or excitatory - consist of chains of 3-40 amino acids.
Important neuropeptides: substance P, dynorphin, hypothalamic regulating hormones, angiotensin 2, cholecystokinin, oxytocin, vasopressin
Synthesis is directed by mRNA on fibosomes - only in dendrites or cell bodies of peptide-secreting neurons.
Synthesis creates large protohormones - then cleaved by proteolytic enzymes - packaged into vesicles in smooth emdoplasmic reticulum - transported to axon terminals for realease
-
Enkephalins
Concentrated in Thalamus, Hypothalamus, parts of Limbic System, and Spinal pathways that relay pain
They suppress Substance P and therefore mediate pain. 200 times stronger than morphine but effects are short lived
Dynorphins
Posterior pituitary gland, hypothalamus, small intestine.
-
-
Substance P
Sensory nerves, spinal cord pathways, parts of brain associated with pain transmission - substansia nigra, basal ganglia, amygdala, hypothalamus, cerebral cortex.
-