Side Of Rabbit Research Articles

Biomechanical changes in the osteonecrosis of the femoral head of rabbits treated by neuropeptide gene-transfected stem cells combined with autologous bone grafting

Objective To investigate the biomechanical changes in the osteonecrosis of the femoral head (ONFH) of rabbits treated by neuropeptide gene (calcitonin gene-related peptide α, hCGRPα)-transfected stem cells combined with autologous bone grafting. Methods The ONFH models on one side in rabbits were established by liquid nitrogen. Forty-eight rabbits ONFH models were randomly divided into 3 groups: group A [hCGRPα-transfected bone marrow mesenchymal stem cell (BMSCs) group], the hCGRPα was transfected into BMSCs combined with autologous bone graft into the femoral head; group B (BMSCs group), BMSCs were transfected with empty plasmid (only pLNCX2 plasmid) combined with autologous bone graft; group C (irrelated sequence group), BMSCs were transfected with irrelated gene combined with autologous bone graft. Animals were sacrificed at 3rd and 6th month respectively to observe the biomechanical changes in the femoral head of rabbits. Results At 3rd month after surgical treatment, in groups A, B, and C the maximum compressive strength and mean elastic modulus of the subchondral bone of femoral head on surgically treated side respectively were (29.13±1.95) and (59.61±2.18), (24.63±1.35) and (48.87±2.15), (25.05±1.34) and (50.13±2.28) mPa, and those of the cancellous bone of femoral head on surgically treated side respectively were (16.41±1.13) and (24.11±2.32), (11.43±1.55) and (17.63±2.45), (12.51±1.85) and (18.22±2.32) mPa. The biomechanical strength was the best in the femoral head in group A, which was nearly close to that in the normal side (P>0.05) and was significantly greater than that in both group B and group C (P 0.05). Conclusion hCGRPα-transfected BMSCs combined with autologous bone grafting into the femoral head of ONFH animal model can accelerate osteogenesis, enhance bone tissue repair, and then effectively recover the normal biomechanical properties of the femoral head. Key words: Calcitonin gene-related peptide; Bone marrow mesenchymal stem cells; Bone grafting; Osteonecrosis of the femoral head; Biomechanics; Rabbit

Effects of carboxyl methylchitosan on hypertrophic scars in rabbit ears

：Objective To investigatethe effect of carboxyl methyl chitosan on hypertrophic scars by establishing ahypertrophic scar model on the ventral side of rabbit ears.Methods Full-thick-nessexcisional wounds,1 cm in diameter,were made in the ears of 12 adult New Zealand whiterabbits,and 123 hypertrophic sears were made in all.Then the rabbits were divided into 3groups:group A was an experimental group (carboxyl methyl chitosan,500μg/ml),group B was a control group1 (triamcinolone),and group C was control group 2 (physiological saline).All the scarswere injected with drugs on the 30th and 40th days after operation,and then the sampleswere collected on the 35th and 45th day and analyzed.Results Compared with group C,group Aappeared to be flatter,softer,and lighter in color;the area density of fibroblastdecreased using HE stain and masson stain (P 0.05).Conclusion Injectionof carboxyl methyl chitosan into Iocal hypertrophic scars On rabbit ears has similareffects to triamcinolone,and both of them can prevent and cure hypertrophic scars inproliferative stage. Key words: Hypertrophic scars; Carboxyl methyl Chitosan; Animal model

Report of the Annual Meeting of the American Rhinologic Society

At the annual meeting of the American Rhinologic Society in Minneapolis, Minn, October 1, 1993, 14 free papers were presented and 10 invited presentations were given in two panel sessions. Maurice Cottle Award was presented to Finn Amble, MD, Minneapolis, Minn, for his paper entitled Mucociliary Function and Endothelins 1, 2, and 3. Endothelins were found to accelerate mucociliary activity through an intermediate prostaglandin pathway, a finding demostrated by in vitro and in vivo analysis. This process is independent of intracellular calcium release. potential of endothelins in respiratory membrane homeostasis and inflammation was reviewed. Resident Research Paper Awards went to D. Randall Pinkston, MD, Iowa City, Iowa, and John E. Buenting, MD, Chapel Hill, NC. Dr Pinkston's paper The Effects of Sinus Surgery on Midfacial Growth in the Rabbit demonstrated restriction in midfacial growth on the operated side in rabbits undergoing maxillary sinus antrostomy, osteoplasty, and uncinectomy.

舌骨上筋群の比較解剖学的研究

Food habit and predation have some effects on the development of the muscles related to mandibular movement. It seems that comparative anatomical studies of muscles and nerves in head and neck is useful. A comparative anatomical study on suprahyoid muscles of six species of mammals was made by means of macroscopy. The mammals in the present study were selected according to the individual food habit : the carnivora (racoon dogs, dogs and cats), the omnivora (pigs) and the herbivora (guinea pigs and rabbits). In a total of 39 mammals, the digastric muscle, stylohyoid muscle, mylohyoid muscle and geniohyoid muscle were observed in gross anatomically for the shape, origin, insertion, direction and innervation. The results were as follows : 1. The digastric muscle arises from the jugular process in racoon dogs, dogs, pigs, guinea pigs and rabbits, from the posterior surface of the mastoid process and the notch between the jugular process and the mastoid process in cats. It inserts into the ventral border of the mandible in all of the species. It appears as a fusiform muscle highly developed in the carnivora. It appears as a double-bellied muscle, or the posterior belly muscle is absent, in the omnivora and the herbivora. The posterior belly is innervated by the facial nerve, and the anterior belly by the mandibular nerve in all of the species. 2. The stylohyoid muscle is absent in racoon dogs and guinea pigs. It arises from the tympanohyoid in dogs and cats, from the stylohyoid in pigs, from the notch between the jugular process and the mastoid process in rabbits. It inserts into the lateral surface of the basihyoid in all of the species. It runs inside the digastric muscle in pigs, and outside the digastric muscle in dogs, cats and rabbits. It is very degenerative in dogs and highly developed in pigs and rabbits. It is innervated by the facial nerve in dogs, cats, pigs and rabbits. 3. The mylohyoid muscle appears as a single sheet in racoon dogs, dogs, cats, pigs and guinea pigs. The anterior muscle bundles arise from the ventral border of the mandible and the posterior muscle bundles from the inner surface of the mandible in racoon dogs and dogs. The both muscle bundles arise from the inner surface of the mandible in cats, pigs and guinea pigs. It appears bilayer, and the superficial layer arises from the ventral border of the mandible, the deep layer from the medial surface of the mandible in rabbits. Almost all the muscle bundles insert into the mylohyiod raphe and other bundles in the posterior portion into the ventral surface of the basihyoid. It is innervated by the mandibular nerve in all of the species. 4. The geniohyoid muscle arises from the inner surface of the mandible adjacent to the mandibular symphysis and inserts into the central portion of the anterior surface of the basihyoid in all of the species. It is a slender and triangular pyramid muscle with the origin at the apex and the insertion at the bottom in all of the specimens. It is in close contact with its counterpart on the opposite side in racoon dogs, dogs, cats and pigs, but not in guinea pigs and rabbits. It is innervated by the hypoglossal nerve in all of the species. 5. The difference of the origin of the digastric muscle and the presence of the degeneration of the stylohyoid muscle among the carnivora seem to be due to the transition of the size or to the relative position with the phylogenetic reconstruction of the stomatognathic system. 6. It seems that the difference of the development of the digastric muscle between the carnivora and the herbivora is due to the difference of their food habits. The more developed the posterior belly muscle of the digastric is, the more degenerated the stylohyoid muscle tends to be in mammals. 7. The lamination of the mylohyoid muscle and no contact with its counterpart on the opposite side in rabbits seem to make the pivoting of the right and left mandibles united

The oxygen consumption of rabbit lung slices after pneumothorax.

We produced a pneumothorax on the left side in rabbits and measured the oxygen consumption of lung slices from previously collapsed left and non-collapsed right lung immediately after in vitro re-expansion. After re-expansion, the oxygen consumptions of the previously collapsed and non-collapsed lung were almost identical, 162 +/- 6.7 and 168.6 +/- 9.6 microliter of oxygen consumed per hour per mg of deoxyribonucleic acid (mean +/- SE), respectively. We concluded that 3 days of collapse does not impair the oxidative metabolism of re-expanded lung.

THE RÔLE OF THE ADRENAL MEDULLA IN THE MAINTENANCE OF BLOOD PRESSURE

Some of the earlier workers investigating the function of the adrenal medulla concluded as a result of their experiments that a constant secretion of adrenaline occurs which helps to maintain the normal blood pressure. Strehl and Weiss (9), who extirpated the adrenal gland on one side in rabbits, found that when the adrenal vein of the other side was clamped the blood pressure immediately fell, and that there was a recovery when the clamps were released. Marked falls of blood pressure were obtained in this way. Young and Lehmann (16) working in Vincent's laboratory repeated the experiments upon dogs but found little, if any, fall of blood pressure. One of the first workers to grow suspicious on this point was Vincent, who was unable to obtain any lowering of blood pressure when the adrenal veins were clamped and a consequent recovery when the clamps were released.