Irradiation of the rat portal vein's fragments with the He-Ne laser for 3, 5 and 10 minutes reduced the fragments tone by half. Frequency of phasic and tonic contractions did not change, their amplitude, however, increased by neatly 40% as compared with the initial level. The NO synthase blocker N-nitro-L-arginine administered prior to the irradiation had no effect on the above parameters. The data obtained suggest that the decrease of the vessel tone is due to production of the EDRF and cGMP. The increase in the amplitude of phasic and tonic contractions of the vein's smooth muscle cells is associated with an increased Ca++ entry in each contraction cycle.

Download full-text PDF

Source

Publication Analysis

Top Keywords

he-ne laser
8
smooth muscle
8
muscle cells
8
phasic tonic
8
tonic contractions
8
[effect he-ne
4
laser irradiation
4
irradiation functional
4
functional activity
4
activity smooth
4

Similar Publications

Compact and full-range carbon dioxide sensor using photoacoustic and resonance dependent modes.

Photoacoustics

February 2025

Dipartimento di Scienze di Base ed Applicate per l'Ingegneria, Sapienza Università di Roma, Rome 00161, Italy.

A compact and robust optical excitation photoacoustic sensor with a self-integrated laser module excitation and an optimized differential resonator was developed to achieve high sensitivity and full linear range detection of carbon dioxide (CO) based on dual modes of wavelength modulated photoacoustic spectroscopy (WMPAS) and resonant frequency tracking (RFT). The integrated laser module equipped with three lasers (a quantum cascade laser (QCL), a distributed feedback laser (DFB) and a He-Ne laser) working in a time-division multiplexing mode was used as an integrated set of spectroscopic sources for detection of the designated concentration levels of CO. With the absorption photoacoustic mode, the WMPAS detection with the QCL and DFB sources was capable of CO detection at concentrations below 20 %, yielding a noise equivalent concentration (NEC) as low as 240 ppt and a normalized noise equivalent absorption coefficient (NNEA) of 4.

View Article and Find Full Text PDF
Article Synopsis
  • * Different exposure times (0 to 3 minutes) showed that most mechanical parameters improved with laser stimulation, indicating stronger seeds, except for a decrease in the force-to-deformation ratio after longer stints.
  • * Findings suggest that using laser stimulation could enhance seed strength, potentially leading to the development of more resilient crops.
View Article and Find Full Text PDF

In this paper, we propose a high-precision dual-comb ranging (DCR) method for short-distance measurement, avoiding carrier-envelope-offset locking. Cross-polarization detection is introduced, which makes better use of the intrinsic coherence of interferogram pairs over a short distance. We analyze the noise in the DCR system and propose a carrier-wave phase difference (CPD) calculation algorithm based on centroid extraction.

View Article and Find Full Text PDF
Article Synopsis
  • Plantar warts, benign growths on the feet caused by HPV, are tough to eliminate completely, often leading to reappearance; this study looks at a dual treatment approach.
  • Data from 10 patients with stubborn warts were analyzed after undergoing a combination of CO laser treatment and 5-ALA photodynamic therapy, yielding a 70% overall lesion clearance rate.
  • This combined therapy proved to be effective and safe, suggesting it could be a good alternative for treating difficult plantar wart cases with minimal side effects.
View Article and Find Full Text PDF

The aqueous solution cast method was used to create the biodegradable polymer nanocomposite (PNC) films from a blend of poly (vinyl alcohol) PVA and poly (vinyl pyrrolidone) PVP (70/30 wt %) and FeO nanoparticles (NPs). These PNC films were characterized using X-ray diffraction, scanning electron microscopy SEM, Fourier transform infrared spectroscopy FTIR, and ultraviolet-visible spectroscopy. XRD and FTIR results indicate that Fe NPs interact with the host polymer.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!