Most insect circulatory physiologists believe the insect heart to be myogenic. There is disagreement, however, about mechanisms regulating heart function. Modulation is considered to occur via either neural or neurohormonal mechanisms but there is little existing data of the type necessary for proving one mechanism or the other. Using the recording technique of impedance conversion, heartbeat patterns were established for intact Honey Bees during rest and also during nectar feeding and locomotion, activities that both result in modulating heartbeat. Heartbeat patterns were then described separately for bees in which assumed neural regulation was disrupted (the ventral nerve cord was transected), and for bees in which assumed neurohormonal regulation was disrupted (blood circulation to the abdomen was blocked). Heartbeat patterns from these latter two groups were then compared with the baseline data from the former three groups. Results showed that normal modulation occurring during feeding and locomotion remained intact when neurohormonal pathways were disrupted, but the same modulation was absent when neural pathways were disrupted. These results offer clear support for the conclusion that neural mechanisms provide a primary form of regulation of heart function in the Honey Bee.
","abstract_html":"<p>Most insect circulatory physiologists believe the insect heart to be myogenic. There is disagreement, however, about mechanisms regulating heart function. Modulation is considered to occur via either neural or neurohormonal mechanisms but there is little existing data of the type necessary for proving one mechanism or the other. Using the recording technique of impedance conversion, heartbeat patterns were established for intact Honey Bees during rest and also during nectar feeding and locomotion, activities that both result in modulating heartbeat. Heartbeat patterns were then described separately for bees in which assumed neural regulation was disrupted (the ventral nerve cord was transected), and for bees in which assumed neurohormonal regulation was disrupted (blood circulation to the abdomen was blocked). Heartbeat patterns from these latter two groups were then compared with the baseline data from the former three groups. Results showed that normal modulation occurring during feeding and locomotion remained intact when neurohormonal pathways were disrupted, but the same modulation was absent when neural pathways were disrupted. These results offer clear support for the conclusion that neural mechanisms provide a primary form of regulation of heart function in the Honey Bee.</p>","abstract_has_math":false,"creators":["Schwab, Ernest R."],"institution":null,"degree_name":"Doctor of Philosophy (PhD)","degree_level":"Dissertation","degree_discipline":"Biology","degree_department":null,"school":null,"contributors":["Robert A. Chilson","Leonard R. Brand","C. Douglas Eddleman","Elwood S. McCluskey","Raymond E. Ryckman"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":1989,"date_issued":"1989-06-01T07:00:00Z","date_published":"1989-06-01T07:00:00Z","updated_at":"2026-07-24T02:53:37Z","subjects":["Biology","Heart Rate; Bees; Neurotransmitters"],"languages":["English"],"rights":["This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholarsrepository.llu.edu/etd/1346","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Robert A. Chilson","Leonard R. Brand","C. Douglas Eddleman","Elwood S. McCluskey","Raymond E. 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The author retains all other copyrights."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholarsrepository.llu.edu/etd/1346"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Most insect circulatory physiologists believe the insect heart to be myogenic. There is disagreement, however, about mechanisms regulating heart function. Modulation is considered to occur via either neural or neurohormonal mechanisms but there is little existing data of the type necessary for proving one mechanism or the other. Using the recording technique of impedance conversion, heartbeat patterns were established for intact Honey Bees during rest and also during nectar feeding and locomotion, activities that both result in modulating heartbeat. Heartbeat patterns were then described separately for bees in which assumed neural regulation was disrupted (the ventral nerve cord was transected), and for bees in which assumed neurohormonal regulation was disrupted (blood circulation to the abdomen was blocked). Heartbeat patterns from these latter two groups were then compared with the baseline data from the former three groups. Results showed that normal modulation occurring during feeding and locomotion remained intact when neurohormonal pathways were disrupted, but the same modulation was absent when neural pathways were disrupted. These results offer clear support for the conclusion that neural mechanisms provide a primary form of regulation of heart function in the Honey Bee.
"]},{"key":"dc:title","label":"Title","values":["Heartbeat rate modulation mediated by the ventral nerve cord in the honey bee, APIS MELLIFERA"]}]}],"canonical_facts":{"dc:contributor":["Robert A. Chilson","Leonard R. Brand","C. Douglas Eddleman","Elwood S. McCluskey","Raymond E. Ryckman"],"dc:creator":["Schwab, Ernest R."],"dc:description.abstract":["Most insect circulatory physiologists believe the insect heart to be myogenic. There is disagreement, however, about mechanisms regulating heart function. Modulation is considered to occur via either neural or neurohormonal mechanisms but there is little existing data of the type necessary for proving one mechanism or the other. Using the recording technique of impedance conversion, heartbeat patterns were established for intact Honey Bees during rest and also during nectar feeding and locomotion, activities that both result in modulating heartbeat. Heartbeat patterns were then described separately for bees in which assumed neural regulation was disrupted (the ventral nerve cord was transected), and for bees in which assumed neurohormonal regulation was disrupted (blood circulation to the abdomen was blocked). Heartbeat patterns from these latter two groups were then compared with the baseline data from the former three groups. Results showed that normal modulation occurring during feeding and locomotion remained intact when neurohormonal pathways were disrupted, but the same modulation was absent when neural pathways were disrupted. These results offer clear support for the conclusion that neural mechanisms provide a primary form of regulation of heart function in the Honey Bee.
"],"dc:identifier":["https://scholarsrepository.llu.edu/etd/1346"],"dc:language":["English"],"dc:rights":["This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights."],"dc:subject":["Biology","Heart Rate; Bees; Neurotransmitters"],"dc:title":["Heartbeat rate modulation mediated by the ventral nerve cord in the honey bee, APIS MELLIFERA"],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Doctor of Philosophy (PhD)"]},"updated_at":"2026-07-24T02:53:37Z"}