Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1432-1912
    Keywords: Prejunctional muscarinic receptors ; Acetylcholine release ; Parasympathetic vasoconstriction ; Methoctramine ; AF-DX 116
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Experiments were carried out on rat isolated perfused hearts with both vagus nerves attached. The acetylcholine stores were labelled with [14C]-choline. The effects of muscarinic receptor antagonists on the [14C]overflow and increase in perfusion pressure evoked by vagus nerve stimulation (10 Hz, 4–10 mA) were studied in order to determine the muscarinic receptor type involved in autoinhibition of acetylcholine release and vagally-induced vasoconstriction in the rat heart. Stimulation of the vagus nerves (1200 pulses) caused an increase in [14C]-overflow and in perfusion pressure which was significantly reduced by hexamethonium 500 μmol/l and abolished by tetrodotoxin 0.3 μmol/l or perfusion with Ca2+-free solution. The fractional rate of evoked [14C]-overflow per pulse upon stimulation at 10 Hz (720 pulses) was doubled in the presence of the non-selective antagonist atropine (0.01–1 μmol/l) as well as in that of the M2-selective compounds methoctramine (0.1 μmol/l) and AF-DX 116 (0.1–1 μmol/l), but remained unaffected by the M3-selective hexahydrosiladifenidol (0.1 μmol/l). The increase in perfusion pressure upon nerve stimulation was reduced by atropine (0.01 μmol/l) or hexahydrosiladifenidol (0.1 μmol/l) to approximately 50% and increased by about 50% in the presence of AF-DX 116 (0.1 μmol/l). The results show that the autoinhibition of acetylcholine release in the rat heart is mediated by M2 receptors. On the other hand, the increase in perfusion pressure upon vagus nerve stimulation is caused by a different muscarinic receptor, more sensitive to hexahydrosiladifenidol than to M2-selective antagonists.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-5233
    Keywords: Diabetes mellitus ; Skin thickness ; Diabetic neuropathy
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Skin thickness on the extremities of patients with diabetes mellitus has been described controversially. Using high resolution ultrasonography, we were able to show a significant increase in skin thickness at the forearm (P〈0.05), thigh (P〈0.001) and lower limb (P〈0.05) of diabetic patients, most prominent at the thigh. No difference in skin thickness was found at the dorsum of the foot. In addition, skin thickness was not related to the duration of diabetes, age or HbA1. A close association was found between diabetic neuropathy and increasing skin thickness. Diabetic patients with neurological disorders had a significant increase in skin thickness versus diabetic patients without neuropathy. The present findings suggest that diabetic neuropathy and abnormalities of connective tissue have a common etiological link in their development or that both are time-dependent processes. Whether changes in capillary blood flow, increase of nonenzymatic glycosylation, polyol accumulation or other metabolic disorders are responsible for these findings remains still to be established.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...