Photochemical Effects of Laser Irradiation on Neuritic Outgrowth of Olfactory Neuroepithelial Explants

Abstract

The photochemical effect of low-intensity laser irradiation (LILI) on the maturation and regeneration of olfactory-Immature estrus day 15 (E15) and olfactory-mature estrus day 22 (E22) rat fetuses was studied. Neuritic outgrowths of olfactory bipolar receptor cells were quantified in olfactory neuroepithelial explants. Explants in the experimental groups were irradiated with a helium-neon laser using different incident energy densities (IEDs). Explants in another group were exposed to fluorescent light. Control explants did not receive laser or fluorescent light irradiation. Neuritic outgrowths were analyzed on a regular basis for 12 days. Analysis of variance was used to evaluate the data. The parameters of neuritic outgrowth in E15 fetuses showed a significant increase of 30% to 50% vs. the control with a single laser irradiation of 0.5 J/cm² IED. The rate of neuritic outgrowth observed in the E22 fetuses was less than in the E15 fetuses. The parameters of neuritic outgrowth in E22 fetuses showed a significant and substantially greater percentage increase than in the E15 fetuses with daily laser irradiations of 0.05 and 0.5 J/cm² IED when compared to the control. The magnitude of these increases appears to be of biological significance as well as statistical significance.

Get full access to this article

View all access options for this article.

References

Mester

. The biomedical effects of laser application. Lasers Surg Med 1985; 5: 31–9.

Mester

. Laser biostimulation in wound-healing. In: Joffe

, ed. Lasers in general surgery. Baltimore: Williams & Wilkins, 1989: 275–84.

Mester

. Wound-healing. Laser Therapy 1989; 1: 7–15.

Abergel

Lyons

Castel

Dwyer

Uitto

. Biostimulation of wound healing by lasers: Experimental approaches in animal models and in fibroblast cultures. J Dermatol Surg Oncol 1987; 13: 127–33.

Vizi

Mester

Tisza

Mester

. Acetylcholine releasing effect of laser irradiation on Auerbach's plexus in guinea-pig ileum. J Neural Transm 1977; 40: 305–8.

Walker

. Temporary suppression of clonus in humans by brief photostimulation. Brain Res 1985; 340: 109–13.

Schwartz

Doron

Erlich

, Effects of low-energy He-Ne laser irradiation on posttraumatic degeneration of adult rabbit optic nerve. Lasers Surg Med 1987; 7: 51–5.

Rochkind

Rousso

Nissan

Villarreal

Barr-Nea

Rees

. Systemic effect of low-power laser irradiation on the peripheral and central nervous system, cutaneous wounds, and burns. Lasers Surg Med 1989; 9: 174–81.

Rochkind

Lubart

. New approach for treatment of peripheral and central nervous system by low-power laser irradiation (Abs). Lasers Surg Med 1990; 3: 108.

10.

Graziadei

PPC

Graziadei

GA Monti

. Neurogenesis and neuron regeneration in the olfactory system of mammals: III. Deafferentation and reinnervation of the olfactory bulb following section of the fila olfactoria in rat. J Neurocytol 1980; 9: 145–62.

11.

Costanzo

. Neural regeneration and functional reconnection following olfactory nerve transection in hamster. Brain Res 1985; 361: 258–66.

12.

Farbman

. Prenatal development of mammalian olfactory receptor cells. Chem Senses 1986; 11: 3–18.

13.

Gonzales

Farbman

Gesteland

. Cell and explant culture of olfactory chemoreceptor cells. J Neurosci Meth 1985; 14: 77–90.

14.

Mester

Snow

. Effects of laser irradiation on immature olfactory neuroepithelial explants from the rat. Laryngoscope 1988; 98: 743–5.

15.

Karu

. Photobiology of low-power laser effects. Health Physics 1989; 56: 691–704.

16.

Tsang

Yew

Hui

BSW

. Further studies on the effect of low-dose laser irradiation on cultured retinal pigment cells of the chick. Acta Anat 1986; 125: 10–13.