Monitoring of nicotine impact in microlymphatics of rat mesentery with time-resolved microscopy.
The aim of the study was to evaluate nicotine-induced microlymphatic responses in rat mesentery in vivo with time-resolved transmission microscopy. Male Fisher rats weighing 150-200 g were used in all experiments. The experiments revealed that changes of lymphatic function under direct nicotine impact (continuous topical application of nicotine in the concentration ranges of 0.001 mM, 10 mM and 100 mM for 15 minutes) were dose- and time-dependent. A nicotine dose of 10 mM caused an immediate short-term constriction of 100% of lymphangions. At the highest concentration of nicotine (100 mM), similar constriction as well as inhibition of lymph flow, local stable constriction of lymph microvessels, stasis in blood microvessels, and disturbances of respiration were observed. Application of chronic nicotine (0.23 ml from a 10 mM solution) injection for 14 days via a miniosmotic pump did not substantially change the function of lymphatic and blood microvessels. Our data show for the first time that the acute effect of nicotine is accompanied by significant changes in microlymphatic function. We conclude that the observed effects are due to the direct action of nicotine on lymphatics. The mechanism by which nicotine induces this response remains to be investigated further.
Galanzha
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EL
Philips Classic Laser Laboratories, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA. EGalanzha@uams.edu
Chowhury
P
P
Tuchim
V V
VV
Zharov
V P
VP
D000818:Animals; D004729:Endothelium, Lymphatic / Q000187:drug effects / Q000502:physiology; D007091:Image Processing, Computer-Assisted; D042601:Lymphatic Vessels / Q000187:drug effects* / Q000502:physiology; D008297:Male; D008643:Mesentery / Q000187:drug effects*; D046529:Microscopy, Electron, Transmission / Q000379:methods; D023421:Models, Animal; D009538:Nicotine / Q000494:pharmacology*; D018722:Nicotinic Agonists / Q000494:pharmacology*; D051381:Rats
D018722:Nicotinic Agonists; D009538:Nicotine