ABSTRACT
Objective: To explore the effect of age on Qingkailing Granules disposition by comparing the pharmacokinetics of geniposide and baicalin in juvenile and adult rats. Methods: A simple and rapid LC-MS/MS method was developed and validated to simultaneously determine geniposide and baicalin in rat plasma after a simple protein precipitation. The analytes were separated on an Agilent ZORBAX Extend-C18 column. The mobile phase consisted of acetonitrile and water with 0.1% (volume percent) formic acid at a flow rate of 0.6 mL/min. The ionization was conducted using an ESI source in negative ion mode. Multiple reaction monitoring was used for quantification at transitions of m/z 445.0 → m/z 268.9 for baicalin, m/z 433.2 → m/z 225.0 for geniposide, m/z 431.0 → m/z 341.0 for vitexin (IS). Juvenile and adult rats were administrated Qingkailing Granules (3 g/kg) orally. Plasma concentrations of baicalin and geniposide were determined by LC-MS/MS. Results: The linear ranges of the analytes were 1–1000 ng/mL for baicalin and 2–2000 ng/mL for geniposide. The method was successfully applied to compare the pharmacokinetics of the analytes between juvenile and adult rats after oral administration of Qingkailing Granules. AUC was bigger in adult rats, while t1/2 was longer in juvenile rats. Conclusion: These results suggested that the absorption and elimination of baicalin and geniposide in juvenile rats was lower than that in adult rats. Additional attention should be paid to the pharmacokinetic difference when Qingkailing Granules were used in children.
ABSTRACT
BACKGROUND: Astrocyte proliferation is an important morphological change in epilepsy. Proliferated glial cells can produce cytokines, and in turn activates JAK/STAT signal transduction to promote glial cell proliferation, which affects the occurrence and recurrence of epilepsy. Astrocytes and signal transduction pathways interact with each other to play a role in the pathogenesis of epilepsy. OBJECTIVE: To investigate the effect of cannabinoid receptor type 2 (CB2R) on the activation of ERK, p38, and JNK proteins in astrocytes and MAPK pathways in juvenile rats with persistent epilepsy. METHODS: Forty healthy male Sprague-Dawley rats (18-21 days old) were randomly divided into four groups: normal control group, epilepsy model group, CB2R agonist JWH133 group, CB2R antagonist AM630 group. The normal control group was given only normal saline. In the other groups, rats were intraperitoneally injected with lithium chloride and pilocarpine to establish epilepsy models, and different interventions were performed. Twenty-four hours after the onset of epilepsy, brain tissues were taken. Co-expression of GFAP and p-ERK, p-p38, and p-JNK in hippocampal tissue was detected by immunofluorescence. Real-time PCR was used to detect the expression of GFAP mRNA in hippocampal tissue. RESULTS AND CONCLUSION: The co-expression of GFAP/p-ERK and GFAP/p-p38 was significantly higher in the epilepsy model group than the normal control group (P < 0.05), significantly lower in the JWH133 group than the epilepsy model group (P < 0.05), and significantly higher in the AM630 group than the JWH133 group (P < 0.05). The co-expression of GFAP/p-JNK was significantly lower in the epilepsy model group than in normal control group (P < 0.05), significantly higher in the JWH133 group than the epilepsy model group (P < 0.05), and significantly lower in the AM630 group than the JWH133 group (P < 0.05). The mRNA expression of GFAP was significantly decreased in the epilepsy model group compared with the normal control group (P < 0.05), significantly increased in the JWH133 group compared with the epilepsy model group (P < 0.05), and significantly reduced in the AM630 group compared with the JWH133 group (P < 0.05). Therefore, CB2R can regulate the expression of ERK, p38, JNK proteins in the MAPK pathway, thereby affecting astrocytes in the hippocampus of juvenile rats with persistent epilepsy.
ABSTRACT
During early life, animals are sensitive to environmental events that may lead to short-term and long-lasting changes in their neurobiology and behavior, which could be related to increased risk for psychopathology. Neonatal handling is an experimental intervention in the mother-infant relationship. Based on previous studies, it is known to decrease rat pups' preference for maternal cues. Handling also reduces social, sexual, and fear behavior in adult animals, which is related to underlying neuroendocrine alterations. One prominent feature of adolescence is the high frequency of social behaviors such as play that appear to be necessary for proper socioemotional development. The objective of the present study was to investigate the effect of repeatedly handling pups on social play behavior during the neonatal period in juvenile Wistar rats. We found that handling consistently decreased pouncing, wrestling, and chasing play behavior on postnatal days (PND) 25, 30, and 35 compared with non-handled juveniles. As expected, sex differences were also found. Consistent with previous studies in infant and adult rats, the neonatal handling procedure also reduced affiliative behaviors in juvenile animals. The precise mechanisms by which this early intervention leads to these alterations in offspring remain to be determined, but the cumulative effects of briefly disrupting the mother-infant relationship that caused the neonatal handling may be one possible explanation.