I have had numerous PRP injections from different doctors. A few times it was the red PRP and a few times it was the clear/yellow. It seems that in either case it took repeated injections to put somewhat of a dent into the pain, and to be honest the results were not quite what I had hoped for. My injures are/were: tennis elbow, quad tendon tear/tendinosis and tendinosis and slight tearing of the infraspinatus. That being said, I have continued to be plagued by what seems to be tendon pain throughout my body (tennis elbow in both elbows, hamstring,brachialis ?? and what seems to be the front deltoid) so I wonder how if systemic issues or genetic issues are making me prone to this and preventing me from responding well to treatment.
PUVA is a special treatment using a photosensitizing drug and timed artificial-light exposure composed of wavelengths of ultraviolet light in the UVA spectrum. The photosensitizing drug in PUVA is called psoralen. Both the psoralen and the UVA light must be administered within one hour of each other for a response to occur. These treatments are usually given in a physician's office two to three times per week. Several weeks of PUVA is usually required before seeing significant results. The light exposure time is gradually increased during each subsequent treatment. Psoralens may be given orally as a pill or topically as a bath or lotion. After a short incubation period, the skin is exposed to a special wavelength of ultraviolet light called UVA. Patients using PUVA are generally sun sensitive and must avoid sun exposure for a period of time after PUVA. Common side effects with PUVA include burning, aging of the skin, increased brown spots called lentigines , and an increased risk of skin cancer , including melanoma . The relative increase in skin cancer risk with PUVA treatment is controversial. PUVA treatments need to be closely monitored by a physician and discontinued when a maximum number of treatments have been reached.
The hormone is synthesized and secreted from alpha cells (α-cells) of the islets of Langerhans , which are located in the endocrine portion of the pancreas. Production, which is otherwise freerunning, is suppressed/regulated by insulin from the adjacent beta cells. When blood sugar drops, insulin production drops and more glucagon is produced  In rodents, the alpha cells are located in the outer rim of the islet. Human islet structure is much less segregated, and alpha cells are distributed throughout the islet in close proximity to beta cells. Glucagon is also produced by alpha cells in the stomach.