Neuroma formation and abnormal afferent nerve discharges after partial beak amputation (beak trimming) in poultry

Summary Following partial amputation of the beak recordings were taken of the electrical activity from single afferent fibers of the intramandibular nerve. A total of 192 single afferent fiber units were isolated of which 47 were classified as nociceptors, with an abnormal pattern of discharge, and 89 were abnormal spontaneously active units. Following amputation neuromas were developing by 15 days after surgery and they were well formed by 20 to 30 days. The presence of neuromas together with abnormal spontaneous activity originating from them raise serious welfare questions concerning beak trimming.Acknowledgment. We thank Louise Hunter for her technical assistance and J. B. is indebted to the AFRC and BEMB for financial support during the tenure of his studentship.     

Polyploidization and production of abnormal spermatids inPsophus stridulus (Orthoptera)

Summary Abnormal spermatids exhibiting variation in the number of adjunct centrioles (ACs) (from two to eight) have been analyzed in a spontaneous mutant grasshopper characterized by a high tendency to form polyploid meiocytes. Results show that the observed polyploidization of these cells increases the number of abnormal gametes and, although diploid spermatids (with two ACs) are the most frequent, higher levels of ploidy are also produced. The variation in the number of ACs, the level of ploidy in the sperm and the presence of polyploid meiocytes, are topics briefly discussed.     

Electric organ discharges of the weakly electric fishGymnarchus niloticus (mormyriformes) in its natural habitat

Summary Electric organ discharges (EODs) ofGymnarchus niloticus in its natural habitat (Chari River, Chad Basin) and accompanying ecological data (pH, conductivity, temperature, turbidity, O₂ dissolved) were recorded. The EOD frequencies ranged from 204 to 313 Hz (day) and 196–326 Hz (night). In social swimming the range of interfish EOD frequency differences was from 4 to 82 Hz. The EOD frequency seems to decrease with the age of the fish.Supported by CUNY/RF No. 10748; Hunter College; American Philosophical Society, Penrose Fund No. 7135.Supported by C. N. R. S./R. C. P.     

Increase in in vivo (3H) spiperone binding in the rat hippocampal formation and striatum after repeated treatment with haloperidol

Summary An increase in in vivo (³H) spiperone binding was observed in rat hippocampal formation and striatum after repeated treatment with haloperidol. This suggests that in hippocampus as well as in striatum prolonged blockade of dopaminergic transmission by a neuroleptic agent results in the development of a supersensitivity of the dopamine receptors.Acknowledgments. We wish to thank Mrs J. Krauss for skillful technical assistance, Drs Helmut Bittiger and Rainer Ortmann for helpful discussions.     

On the origin of small adrenergic storage vesicles: Evidence for local formation in nerve endings after chronic reserpine treatment

Zusammenfassung Die adrenergen Nervenendigungen der von Ratten, die während 6 Tagen Reserpin Iris erhalten haben, enthalten eine höhere Anzahl von länglichen synaptischen Vesikeln und Tubuli als diejenigen unbehandelter Kontrolltiere. Die Möglichkeit, dass die adrenergen Bläschen unter gewissen Umständen in den Nervenendigungen gebildet werden könnten, wird diskutiert.     

Cobalt-staining of motor nerve endings in the locust (Locusta migratoria)

Summary A method is described for axonal cobalt-staining of peripheral nerve branches. First experiments were carried out on abdominal muscles of the locust.     

Neurosecretory cells in the ventral nerve cord of leech (Hirudinaria granulosa)

Zusammenfassung Nachweis von 3 Typen neurosekretorischer Zellen im Bauchmark der indischen BlutegelHirudinaria granulosa undTheromyzon rude.     

DNA synthesis in exocrine and endocrine pancreas after partial hepatectomy in Syrian golden hamsters

Summary ³H-thymidine autoradiography showed an enhanced DNA synthesis, in acinar and islet cells of pancreas after partial hepatectomy in syrian golden hamsters. A significant nuclear labeling index of acinar cells was observed between 48 and 84 h and reached control levels by 120 h. An increased labeling index of islet cells was also observed, however, this increase was not statistically significant. These results indicate growth factor(s) produced after partial hepatectomy is capable of inducing DNA synthesis in pancreas.This work is supported by NIH grant CA 36043.     

DNA synthesis in exocrine and endocrine pancreas after partial hepatectomy in Syrian golden hamsters

3H-thymidine autoradiography showed an enhanced DNA synthesis in acinar and islet cells of pancreas after partial hepatectomy in syrian golden hamsters. A significant nuclear labeling index of acinar cells was observed between 48 and 84 h and reached control levels by 120 h. An increased labeling index of islet cells was also observed, however, this increase was not statistically significant. These results indicate growth factor(s) produced after partial hepatectomy is capable of inducing DNA synthesis in pancreas.     

Monoamine-containing structures in the nerve cord of some representatives of diptera (Insecta)

Zusammenfassung Mit Hilfe einer fluoreszenzmikroskopischen Methode wird an zwei Nematocera (S. argyreatum undP. contaminata) gezeigt, dass bestimmte Stellen des Unterschlundganglions und die Ventralganglien biogene Monoamine (wahrscheinlich Dopamin und Noradrenalin) enthalten. Adrenergische Nervenfasern wurden auch in den Konnektiven nachgewiesen.