Marked occurrence of receptors for sympathetic and cholinergic transmitters and for substance P in the blood vessels of the human patellar tendon.
2005 (English)Conference paper (Refereed)
INTRODUCTION: Human tendons have generally been considered to be hyponeural. However, in our recent studies of the patellar tendon in both healthy individuals and patients with tendinosis (jumper’s knee), we have noted the presence of general (PGP 9.5) and sensory (substance P [SP]) innervations, especially in the loose paratendinous connective tissue. Furthermore, we have observed a pronounced expression of the neurokinin-1 receptor (the preferred receptor for SP) in blood vessel walls. The findings are of interest as a new successful treatment of tendinosis has emerged in form of doppler guided sclerosing injections (substance: Polidokanol), targeting areas with neovascularisation, and as SP is known to be of importance when neurogenic angiogenesis participates in diseases. AIM: To further investigate the blood vessels of the normal and tendinosis-affected human patellar tendon regarding autonomic innervation. METHODS: Immunohistochemistry and histochemistry, including antibodies against the sympathetic nerve markers tyroxine hydroxylase and neuropeptide Y and against various adrenoreceptors (α1, α2a, β1), as well as stainings for substances related to cholinergic functions such as the muscarinic M2 receptor, acetylcholinesterase and vesicular acetylcholine transporter. RESULTS/CONCLUSIONS: The preliminary results so far, indicate that there is indeed an occurrence of both sympathetic and cholinergic innervations in the tendon, not the least shown via the presence of sympathetic and cholinergic receptors in blood vessel walls; a fact that further supports the theories that blood vessel regulation via neurotransmitters/-modulators might be a key factor in the pathological mechanisms of jumper’s knee.
Place, publisher, year, edition, pages
IdentifiersURN: urn:nbn:se:umu:diva-20415OAI: oai:DiVA.org:umu-20415DiVA: diva2:208647
European Neuropeptide Club 15th Annual Meeting 2005