title: Sedative and anticonvulsant activities of styrax after oral and intranasal administration in mice.
abstract: BACKGROUND
  Styrax, resin of Liquidambar orientalis Mill. (N.O. Hamamelaceae), belongs to resuscitation-inducing aromatic herbs in traditional Chinese medicine and functions in inducing resuscitation and restoring conscientiousness.
  
  
  OBJECTIVE
  The possible sedative and anticonvulsant activities of styrax on CNS were investigated. The onsets of action of two different routes (oral and intranasal administration) were compared.
  
  
  METHODS
  Styrax was tested for sedative, hypnotic, and anticonvulsant effects using locomotor activity evaluation, pentobarbital-induced sleeping time, and pentylenetetrazol (PTZ)-induced convulsion, respectively.
  
  
  RESULTS
  After oral administration (25, 50, 100 mg/kg), styrax prolonged the sodium pentobarbital-induced sleeping time. In comparison with oral administration, intranasal administration (12.5, 25, 50 mg/kg) prolonged the sleeping time at lower dosage. Moreover, styrax (100 and 200 mg/kg) promoted a significant protection against PTZ-induced seizures and mortality 30 min after oral administration. In contrast, 5 min after intranasal administration, styrax promoted significant protection at lower dosages (25 and 50 mg/kg). These data show that styrax had faster onset of action (5 vs. 30 min) and better anticonvulsant efficacy (25, 50 vs. 100, 200 mg/kg) by intranasal route in comparison with that by intragastric route. Styrax decreased the spontaneous locomotor movements at 100 mg/kg during 5-60 min interval after oral administration.
  
  
  CONCLUSIONS
  Styrax has sedative and anticonvulsant activities. Furthermore, styrax has faster onset of action as well as more potent efficacy after intranasal administration at lower dosage than by intragastric route. This result illustrates that intranasal administration may act as a promising alternative to conventional routes of administration.
authors.affiliation: Jiangsu Key laboratory for TCM formulae Research, Nanjing University of Chinese Medicine, Nanjing, P.R. China.
authors.forename: Jianming
authors.initials: J
authors.lastname: Guo
authors.forename: Jin-Ao
authors.initials: JA
authors.lastname: Duan
authors.forename: Yuping
authors.initials: Y
authors.lastname: Tang
authors.forename: Yawen
authors.initials: Y
authors.lastname: Li
mesh_terms: D000281:Administration, Intranasal; D000284:Administration, Oral; D000818:Animals; D000927:Anticonvulsants / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical; D006993:Hypnotics and Sedatives / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009043:Motor Activity / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D012640:Seizures / Q000517:prevention & control; D012890:Sleep / Q000187:drug effects; D032362:Styrax; D013997:Time Factors
chemical_list: D000927:Anticonvulsants; D006993:Hypnotics and Sedatives; D010936:Plant Extracts