{"id":{"repo_id":"birmingham","oai_identifier":"oai:etheses.bham.ac.uk:630"},"canonical_url":"https://search.dev.ndltd.org/etd/birmingham/oai:etheses.bham.ac.uk:630","repository":{"repo_id":"birmingham","name":"University of Birmingham","base_url":"https://etheses.bham.ac.uk/cgi/oai2"},"display":{"title":"The response of human spermatozoa to chemoattractants","abstract":"The effect of the chemoattractant bourgeonal on [Ca\\(^{2+}\\)]i and chemotaxis in human sperm was investigated. Burgeonal induced a dose-dependent, slowly-developing tonic elevation in [Ca\\(^{2+}\\)]i, The response was dependent on capacitation. In low-Ca\\(^{2+}\\) or EGTA-buffered saline the response to bourgeonal was inhibited. Pretreating spermatozoa with bis-phenol (20μM) to release stored Ca\\(^{2+}\\) did not alter the response. Thus bourgeonal acts primarily by inducing Ca\\(^{2+}\\) influx. Treatment of sperm with bourgeonal caused an increase in [cAMP]. When cells were pretreted with bourgeonal in low-Ca\\(^{2+}\\)saline, subsequent introduction of Ca\\(^{2+}\\) resulted in a single, large [Ca\\(^{2+}\\)]i transient in >75% of the cells, indicating that sudden influx of Ca\\(^{2+}\\) caused closure of the bourgeonal-sensitive Ca\\(^{2+}\\)- channel. This negative feedback was not modulated by IBMX (1mM) or dbcAMP (1mM), indicating that cAMP was not involved and that a direct action Ca\\(^{2+}\\) was more likely. Both Ni\\(^{2+}\\) (10μM) and La\\(^{3+}\\) (100μM) inhibited the action of bourgeonal on [Ca\\(^{2+}\\)]i, suggesting a possible role of CNG channels. Exposing sperm to a temporal bourgeonal gradient caused a series of transient [Ca\\(^{2+}\\)]i elevations in >20% of the cells. A gradient of progesterone (another characterised chemoattractant for human sperm) induced similar Ca\\(^{2+}\\) oscillations (in >20% of the cells), which increased in amplitude and frequency in response to the increasing progesterone concentration. Human spermatozoa responded chemotactically to a 1nM bourgeonal gradient, Chemotaxis was dependent on capacitation. The response was inhibited in low [Ca\\(^{2+}\\)]o but was unaltered by TMB-8 (an inhibitor of stored Ca\\(^{2+}\\) store release), thus showing a dependence on Ca\\(^{2+}\\) influx similar to the [Ca\\(^{2+}\\)]i signal.","abstract_html":"The effect of the chemoattractant bourgeonal on [Ca<span class=\"etd-inline-math\"><sup>2+</sup></span>]i and chemotaxis in human sperm was investigated. Burgeonal induced a dose-dependent, slowly-developing tonic elevation in [Ca<span class=\"etd-inline-math\"><sup>2+</sup></span>]i, The response was dependent on capacitation. In low-Ca<span class=\"etd-inline-math\"><sup>2+</sup></span> or EGTA-buffered saline the response to bourgeonal was inhibited. Pretreating spermatozoa with bis-phenol (20μM) to release stored Ca<span class=\"etd-inline-math\"><sup>2+</sup></span> did not alter the response. Thus bourgeonal acts primarily by inducing Ca<span class=\"etd-inline-math\"><sup>2+</sup></span> influx. Treatment of sperm with bourgeonal caused an increase in [cAMP]. When cells were pretreted with bourgeonal in low-Ca<span class=\"etd-inline-math\"><sup>2+</sup></span>saline, subsequent introduction of Ca<span class=\"etd-inline-math\"><sup>2+</sup></span> resulted in a single, large [Ca<span class=\"etd-inline-math\"><sup>2+</sup></span>]i transient in &gt;75% of the cells, indicating that sudden influx of Ca<span class=\"etd-inline-math\"><sup>2+</sup></span> caused closure of the bourgeonal-sensitive Ca<span class=\"etd-inline-math\"><sup>2+</sup></span>- channel. This negative feedback was not modulated by IBMX (1mM) or dbcAMP (1mM), indicating that cAMP was not involved and that a direct action Ca<span class=\"etd-inline-math\"><sup>2+</sup></span> was more likely. Both Ni<span class=\"etd-inline-math\"><sup>2+</sup></span> (10μM) and La<span class=\"etd-inline-math\"><sup>3+</sup></span> (100μM) inhibited the action of bourgeonal on [Ca<span class=\"etd-inline-math\"><sup>2+</sup></span>]i, suggesting a possible role of CNG channels. Exposing sperm to a temporal bourgeonal gradient caused a series of transient [Ca<span class=\"etd-inline-math\"><sup>2+</sup></span>]i elevations in &gt;20% of the cells. A gradient of progesterone (another characterised chemoattractant for human sperm) induced similar Ca<span class=\"etd-inline-math\"><sup>2+</sup></span> oscillations (in &gt;20% of the cells), which increased in amplitude and frequency in response to the increasing progesterone concentration. Human spermatozoa responded chemotactically to a 1nM bourgeonal gradient, Chemotaxis was dependent on capacitation. The response was inhibited in low [Ca<span class=\"etd-inline-math\"><sup>2+</sup></span>]o but was unaltered by TMB-8 (an inhibitor of stored Ca<span class=\"etd-inline-math\"><sup>2+</sup></span> store release), thus showing a dependence on Ca<span class=\"etd-inline-math\"><sup>2+</sup></span> influx similar to the [Ca<span class=\"etd-inline-math\"><sup>2+</sup></span>]i signal.","abstract_has_math":true,"creators":["Morales Garcia, Auden Andres"],"institution":"University of Birmingham","degree_name":"d_ph","degree_level":"d_ph","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2010,"date_issued":"2010-07","date_published":"2010-07","updated_at":"2026-07-24T01:11:02Z","subjects":["QH301 Biology"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.sponsor","label":"Sponsor","values":["na"]},{"key":"dc:creator","label":"Author","values":["Morales Garcia, Auden Andres"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2010-07"]},{"key":"dc:date.issued","label":"Date","values":["2010-07"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["College of Life & Environmental Sciences","School of Biosciences"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Birmingham"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["http://etheses.bham.ac.uk//id/eprint/630/"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["d_ph"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["d_ph"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["QH301 Biology"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://etheses.bham.ac.uk//id/eprint/630/1/MoralesGarcia10PhD.pdf","http://etheses.bham.ac.uk//id/eprint/630/2/Decl_IS_MoralesGarcia10PhD.pdf"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The effect of the chemoattractant bourgeonal on [Ca\\(^{2+}\\)]i and chemotaxis in human sperm was investigated. Burgeonal induced a dose-dependent, slowly-developing tonic elevation in [Ca\\(^{2+}\\)]i, The response was dependent on capacitation. In low-Ca\\(^{2+}\\) or EGTA-buffered saline the response to bourgeonal was inhibited. Pretreating spermatozoa with bis-phenol (20μM) to release stored Ca\\(^{2+}\\) did not alter the response. Thus bourgeonal acts primarily by inducing Ca\\(^{2+}\\) influx. Treatment of sperm with bourgeonal caused an increase in [cAMP]. When cells were pretreted with bourgeonal in low-Ca\\(^{2+}\\)saline, subsequent introduction of Ca\\(^{2+}\\) resulted in a single, large [Ca\\(^{2+}\\)]i transient in >75% of the cells, indicating that sudden influx of Ca\\(^{2+}\\) caused closure of the bourgeonal-sensitive Ca\\(^{2+}\\)- channel. This negative feedback was not modulated by IBMX (1mM) or dbcAMP (1mM), indicating that cAMP was not involved and that a direct action Ca\\(^{2+}\\) was more likely. Both Ni\\(^{2+}\\) (10μM) and La\\(^{3+}\\) (100μM) inhibited the action of bourgeonal on [Ca\\(^{2+}\\)]i, suggesting a possible role of CNG channels. Exposing sperm to a temporal bourgeonal gradient caused a series of transient [Ca\\(^{2+}\\)]i elevations in >20% of the cells. A gradient of progesterone (another characterised chemoattractant for human sperm) induced similar Ca\\(^{2+}\\) oscillations (in >20% of the cells), which increased in amplitude and frequency in response to the increasing progesterone concentration. Human spermatozoa responded chemotactically to a 1nM bourgeonal gradient, Chemotaxis was dependent on capacitation. The response was inhibited in low [Ca\\(^{2+}\\)]o but was unaltered by TMB-8 (an inhibitor of stored Ca\\(^{2+}\\) store release), thus showing a dependence on Ca\\(^{2+}\\) influx similar to the [Ca\\(^{2+}\\)]i signal."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["The response of human spermatozoa to chemoattractants"]}]}],"canonical_facts":{"dc:contributor.sponsor":["na"],"dc:creator":["Morales Garcia, Auden Andres"],"dc:date":["2010-07"],"dc:date.issued":["2010-07"],"dc:description.abstract":["The effect of the chemoattractant bourgeonal on [Ca\\(^{2+}\\)]i and chemotaxis in human sperm was investigated. Burgeonal induced a dose-dependent, slowly-developing tonic elevation in [Ca\\(^{2+}\\)]i, The response was dependent on capacitation. In low-Ca\\(^{2+}\\) or EGTA-buffered saline the response to bourgeonal was inhibited. Pretreating spermatozoa with bis-phenol (20μM) to release stored Ca\\(^{2+}\\) did not alter the response. Thus bourgeonal acts primarily by inducing Ca\\(^{2+}\\) influx. Treatment of sperm with bourgeonal caused an increase in [cAMP]. When cells were pretreted with bourgeonal in low-Ca\\(^{2+}\\)saline, subsequent introduction of Ca\\(^{2+}\\) resulted in a single, large [Ca\\(^{2+}\\)]i transient in >75% of the cells, indicating that sudden influx of Ca\\(^{2+}\\) caused closure of the bourgeonal-sensitive Ca\\(^{2+}\\)- channel. This negative feedback was not modulated by IBMX (1mM) or dbcAMP (1mM), indicating that cAMP was not involved and that a direct action Ca\\(^{2+}\\) was more likely. Both Ni\\(^{2+}\\) (10μM) and La\\(^{3+}\\) (100μM) inhibited the action of bourgeonal on [Ca\\(^{2+}\\)]i, suggesting a possible role of CNG channels. Exposing sperm to a temporal bourgeonal gradient caused a series of transient [Ca\\(^{2+}\\)]i elevations in >20% of the cells. A gradient of progesterone (another characterised chemoattractant for human sperm) induced similar Ca\\(^{2+}\\) oscillations (in >20% of the cells), which increased in amplitude and frequency in response to the increasing progesterone concentration. Human spermatozoa responded chemotactically to a 1nM bourgeonal gradient, Chemotaxis was dependent on capacitation. The response was inhibited in low [Ca\\(^{2+}\\)]o but was unaltered by TMB-8 (an inhibitor of stored Ca\\(^{2+}\\) store release), thus showing a dependence on Ca\\(^{2+}\\) influx similar to the [Ca\\(^{2+}\\)]i signal."],"dc:format":["application/pdf"],"dc:identifier.uri":["http://etheses.bham.ac.uk//id/eprint/630/1/MoralesGarcia10PhD.pdf","http://etheses.bham.ac.uk//id/eprint/630/2/Decl_IS_MoralesGarcia10PhD.pdf"],"dc:publisher.department":["College of Life & Environmental Sciences","School of Biosciences"],"dc:publisher.institution":["University of Birmingham"],"dc:relation.isreferencedby":["http://etheses.bham.ac.uk//id/eprint/630/"],"dc:subject":["QH301 Biology"],"dc:title":["The response of human spermatozoa to chemoattractants"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["d_ph"],"dc:type.qualificationname":["d_ph"]},"updated_at":"2026-07-24T01:11:02Z"}