Effect of laser irradiation on the growth and development of fetal mouse limbs in an in vitro model

✍ Scribed by Thawer, Habiba A.; Houghton, Pamela E.

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 515 KB
• Volume: 24
• Category: Article
• ISSN: 0196-8092
• DOI: 10.1002/(sici)1096-9101(1999)24:4<285::aid-lsm6>3.0.co;2-m

✦ Synopsis

Background and Objective:

The purpose of the present study was to examine the effects of laser irradiation on the growth and development of fetal limb tissue. Study Design/Materials and Methods: Day 14 fetal mouse limbs (n = 168) were irradiated with gallium arsenide laser (904 nm, spot size = 0.002 cm 2 , pulse duration = 200 nanoseconds, peak power = 30 mW) for 1 minute each day while being maintained in an organ culture system for 3 or 5 days at the following energy densities [0 (control), 0.23, 1.37, 2.75, 3.66, and 4.58 J/cm 2 ]. Results: Computer image analysis of photographic images showed that there was a significant inhibition (P < 0.05) of new tissue growth after administration of lower energy densities of laser (0.23 and 1.37 J/cm 2 ). These low-energy densities of laser irradiation also produced increased dermal cell number and collagen fiber thickness as assessed with qualitative histologic analysis of limb development by a blinded observer. Quantitative analysis of collagen distribution by color densitometric analysis of tissue sections stained with sirus red and fast green confirmed that there was a significantly greater (P < 0.05) amount of collagen present in the dermis of limbs treated with low-energy densities of laser (0.23 and 1.37 J/cm 2 ). Conclusions: Laser irradiation directly affected the growth and development of day 14 fetal mouse limbs in an organ culture system.