Oct 21 (Reuters) - Pacific Sunwear of California Inc on Tuesday, October 21st said it rejected an unsolicited buyout offer from athletic-clothing retailer Adrenalina , saying the proposal was not in the best interests of its shareholders.

PacSun collection

The decision comes a day after Adrenalina made an offer to buy larger rival PacSun for $4.50 a share in a cash and stock deal, valuing the struggling teen retailer at about $295 million.

PacSun, a surfing-inspired apparel chain with more than 1,000 stores, had earlier thwarted several attempts by the smaller rival to coax PacSun Chief Executive Sally Frame Kasaks to enter into discussions.

Adrenalina, which had sales of $2.3 million in the six months ended June 30, operates about three stores in Florida.

PacSun shares were down 6 cents at $3.74 in afternoon trading on Nasdaq. (Reporting by Dhanya Skariachan in Bangalore; Editing by Vinu Pilakkott)