EFFECT OF ACETYLCHOLINIC AND ADRENAL BLOCKADE ON THE MAXILLARY GROWTH DURING EXPERIMENTAL WOUND PROCESS IN RATS’ HARD PALATE

Khripachenko M.

CONTENTS

Scentific article

After initial surgical treatment of children cleft palate, there are disturbances of the maxilla growth and development. Among factors that affect to this disturbances progress, apart from defect itself, which inherent in disease, and functional deformation, which involved in process initially, the main is postsurgical wound healing process in hard palate. Solid evidence of iatrogenic factors participation in this process is, at the end of the day, “un-touched” growth of maxilla in patients who are not achieved treatment. The result of wound healing in hard palate is scar tissue formation and qualitative characteristics of this one most probably defined level of maxillary growth disturbances. Wound healing and as a results quality of scar formation depend upon state (tonus and reactivity) of autonomic nervous systems, which influences realized through adrenal and cholinergic receptors. We perform our study to test hypothesis about autonomic nervous system tonus and reactivity influences on the maxillary growth and development in the condition of experimental hard palate postsurgical scar formation. With approval of Donetsk national medical university ethical commission according to international regulation and recommendation for working with laboratory animals, we perform the experiments using 30 Wistar line laboratory white rats in three groups up to 10 animals in each group. For all animals in the age of 21 days, under standard general anesthesia (thiopental 40 mg/kg, i. p.) we simulate postsurgical wound of hard palate by mucous and periosteal denudation of palate bone. In postoperative period for first group animals, we inject atropine in the dose of 0. 05 mg/kg body weight subcutaneously, with the goal of nonselective blockade of acetylcholine receptors. For the second group of animals we perform blockade of adrenergic receptors by using subcutaneous injection of labetalol in the dose of 10 mg/kg of animal body weight. Duration of pharmacological blockade was 56 days, after this period we perform Cone Beam Computed Tomography and determine sizes of maxilla according to work out methods. The third group with natural tonus and reactivity of autonomic nervous system serves as control group. It was established, that after completion of maxillary growth in animal of control group the width of palate was (Me(min-max)) 6. 83 (5. 9 – 7. 0) mm, width of dental arc was 7. 36 (6. 4 – 7. 6) mm, and degree of dental slope was 0. 52 (0. 3 – 0. 6)mm, accordingly. In the condition of acetylcholine receptors blockade (first group) width of palate was (Me (min-max)) 5. 82 (5. 6-6. 6) mm, width of dental arc was 6. 23 (5. 9-7. 1) mm, and degree of dental slope was 0. 42 (0. 3-0. 6) mm, accordingly. . In the condition of adrenergic receptors blockade (second group) width of palate was (Me (min-max)) 5. 7 (5. 4-6. 3) mm, width of dental arc was 6. 2 (5. 8-6. 6) mm, and degree of dental slope was 0. 40 (0. 3-0. 5) mm, accordingly. Revealed differences versus control according to Mann-Whitney test statistically significant (p<0. 05). Findings of our study allow us to conclude that wound process, which we design in experimental conditions definitely influence on the maxillary growth, and in animals with acetylcholine receptors blockade this influence express more than in animals with adrenergic receptors blockade.

cleft palate, maxillary development

• Derijcke A. Dental arch dimensions in unoperated adult cleft-palate patients: an analysis of 37 cases / A. Derijcke, Anne M. Kuijpers-Jagtman, C. Lekkas, [et al.] // J. Craniofac. Genet. Dev. Biol. – 1994. – Vol. 4, №1. – P. 69-74.
• Hanna Kasandra R. An update on wound healing and the nervous system / Kasandra R. Hanna, Adam J. Katz // Ann. Plast. Surg. – 2011. – Vol. 67, №. 1 – P. 49–52.
• Kim T. Constriction of the maxillary dental arch by mucoperiosteal denudation of the palate / T. Kim, H. Ishikawa, S. Chu [et al.] // Cleft Palate Craniofacial J. – 2002. – Vol. 39, №. 4. – P. 425–431.
• Kuijpers-Jagtman Anne M. State of the art: The influence of surgery and orthopedic treatment on maxillofacial growth and maxillary arch dimensions in patients treated for orofacial clefts / Anne M. Kuijpers-Jagtman, Ross E. Long // Cleft Palate-Craniofac J. – 2000. – Vol. 37, №. 6. – P. 527/1–527/12.
• Ross R. B. Treatment variables affecting facial growth in complete unilateral cleft lip and palate / R. B. Ross // Cleft Palate J. – 1987. – Vol. 24, № 1. – P. 5–77.
• Whishaw Ian Q. The behavior of the laboratory rat / Ian Q. Whishaw, B. Kolb. – New York : Oxford University Press, 2005. – 504 p.
• Yang Y. Alteration of maxillary and mandibular growth of adult patients with unoperated isolated cleft palate / Y. Yang, Y. Wu, Y. Gu [et al.] // J. Craniofac. Surg. – 2013. – Vol. 24, №4. – P. 1078–1082.
• Ye B. A comparative study on dental-arch morphology in adult unoperated and operated cleft palate patients / B. Ye, C. Ruan, J. Hu [et al.] // J. Craniofac. Surg. – 2010. – Vol. 21, №3. – P. 811–815.

«Bulletin of problems biology and medicine» Issue 2 part 2 (108), 2014 year, 208-212 pages, index UDK 591. 471. 434-001:599. 323. 45]:612. 181. 6-028. 77